🗓️ FHE.org Software Day is next month

FHE.org Software Day takes place next month, on September 24, 2026. This week we began announcing our speaker line-up, starting with Kim Laine!

Kim is a principal researcher in the Cryptography Group at Microsoft Research. He started working on FHE in 2015 and has since been the main developer and maintainer of the Microsoft SEAL library. His talk, Ten Years of SEAL: What I Learned from Building an FHE Library, is one not to miss. More speaker announcements are on the way.

Full details are on the event page: https://fhe.org/softwareday2026 and don’t forget to register here.

📢 FHE.org 2027 Call for Presentations is now open

The call for presentations for the FHE.org 2027 Conference is now open. As usual, we’re seeking talks and posters for the conference, which will be held on April 4, 2027 in Seattle. Submissions should be 2–4 page PDFs. Work already presented elsewhere is welcome, as are demos, tutorials, and anything else the community would find interesting! Submission deadline: November 1, 2026 (AoE).

Full instructions: https://fhe.org/2027/cfp

Interested in sponsoring FHE.org 2027? Reach out to us at contact@fhe.org.

🌐 Community Updates and Academic Conferences

HEIR was showcased on the Google Security blog: How Google is making private AI practical with homomorphic encryption. Alongside the post, the authors have converted the google/fully-homomorphic-encryption repository into a demos repo, including some larger models you can compile and run with HEIR. Check it out!

Crypto 2026 was held in Santa Barbara, California, this month and there were several FHE-based works presented:

• Multi-key Fully Homomorphic Encryption with Non-Interactive Setup in the Plain Model by Seonhong Min, Jeongeun Park, and Yongsoo Song

• Fully-Succinct Multi-Key FHE & Rate-1 Simulatable Threshold Decryption from LWE by Abtin Afshar and Rishab Goyal

• FHE for SIMD Arithmetic Logic Units with Amortized O(1) Bootstrapping per Ciphertext by Mingyu Gao and Hongren Zheng

• SMOOTHIE: (Multi-)Scalar Multiplication Optimisations On TFHE by Xander Pottier, Jan-Pieter D’Anvers, Thomas de Ruijter, and Ingrid Verbauwhede

• High-Precision Exact FHE Made Simple, General, and Fast by Chris Peikert, Doron Zarchy, and Guy Zyskind

• New Techniques for Fast and Shallow FHE Bootstrapping and Beyond by Aayush Jain, Huijia Lin, Zeyu Liu, and Sagnik Saha

• Fully Homomorphic Encryption for Matrix Arithmetic by Craig Gentry and Yongwoo Lee

• Efficient Bootstrapping in Fully Homomorphic Encryption for Matrix Arithmetic by Eric Crockett, Craig Gentry, Hyojun Kim, Yeongmin Lee, and Yongwoo Lee

• Fast Batch Matrix Multiplication in Ciphertexts by Jung Hee Cheon, Minsik Kang, and Junho Lee

• Faster Polynomial Evaluations for SIMD FHEs and Application to BGV in HElib by Jiachen Zhao, Jiang Zhang, Binwu Xiang, Songyu Wu, Yi Deng, and Dengguo Feng 

📰🕺 Latest Updates from the FHE.org Community

• Updates to the FHE.org resources page:

  • How Google is Making Private AI Practical with Homomorphic Encryption by Jeremy Kun

  • Check out all of the resources posted on our website here: https://fhe.org/resources/

• FHE.org Community:

  • Do you have an idea, something to share, a resource to add, or something you’d like to change about FHE.org? You can post any suggestions and proposals in the #meta channel on the FHE.org discord!

  • Interested in joining a reading group? Join the paper reading group in #reading-group. Introduce yourself there to get started!

• Don’t forget that the FHE.org website is open source and that anyone can add resources by simply opening a PR on Github: https://github.com/FHE-org/fhe-org.github.io.

💙 FHE.org is an open-source community of researchers and developers interested in Fully Homomorphic Encryption (FHE), if you’d like to contribute, join the community:

• On Discord

• On X

• On Linkedin

• On Mastodon

• On Bluesky

• On Reddit

• On the official website

👉 Think something is missing from this FHE.org digest? Help us craft the next one, join the discussion on Discord.

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📅 FHE.org Conference 2027 Program Chairs Confirmed

This past month, we announced that David Archer (Niobium) and Rachel Payer (RHUL) will be Program co-chairs of our 2027 conference. We thank our advisory board for selecting the chairs. Keep an eye on our social media channels for further updates about tickets, the call for papers, and other news!

As a reminder, the sixth edition of the FHE.org conference will be held in Seattle, USA, on the 4th of April 2027. This aligns as usual with Real World Crypto 2027, to be hosted by AWS, held immediately after FHE.org. The FHE.org 2027 conference website is already online at https://fhe.org/2027/.

📅 Miran Kim joins FHE.org Advisory Board

We are excited to announce that Miran Kim has agreed to join the FHE.org advisory board. The advisory board meets annually to provide oversight and direction to the FHE.org initiative.

Miran is an associate professor in the Department of Mathematics and is affiliated with the Department of Computer Science at Hanyang University in Korea. She received her PhD in mathematical sciences from Seoul National University, Korea, in 2017. During her PhD she co-authored the CKKS FHE scheme, one of the most widely used FHE schemes in practice today. Her research focuses on the design of novel strategies for secure and privacy-preserving data analysis using homomorphic encryption. She has extensive experience in the algorithmic optimization of homomorphic encryption, as well as in the design and implementation of efficient protocols for data query processing, genomic data analysis, and machine learning. Miran has received various honours and awards throughout her career, including being part of the winning team of the iDash competition three times. Miran’s webpage can be found here.

Miran replaces Damien Stehlé, who served on the advisory board since its inception in 2023. We thank Damien for his contribution over these past three years!

More information on our advisory board can be found on our website.

🎓 Academic Conferences

There were several academic conferences this past month, and many interesting works on FHE were presented.

The inaugural Cedarcrypt event, which was an applied cryptography summer school and conference held July 13–16 in Paphos, Cyprus, had a talk on FHE:

• FHE: from Theory to Practice by Emad Heydari Beni (Nokia Bell Labs, KU Leuven)

Afriacrypt was held July 8-10 in Hammamet, Tunisia, and there were two papers presented on FHE:

• Threshold (T)FHE without smudging by means of correct threshold additive HE by: Antonina Bondarchuk, Renaud Sirdey, Aymen Boudguiga and Olive Chakraborty (Université Paris-Saclay, CEA LIST, Palaiseau, France)

• Minimizing noise growth for TFHE bootstrapping by: Anas Boudi and Louis Goubin (UVSQ Université de Versailles Saint-Quentin-en-Yvelines)

The Workshop on Encrypted Computing & Applied Homomorphic Cryptography (WAHC) 2026 submission deadline was also this past month. The conference will be held at The Hague, The Netherlands, alongside CCS 2026 on November 19th, 2026. Check out the conference webpage here for more details.

📰🕺 Latest Updates from the FHE.org Community

• Updates to the FHE.org resources page:

  • End-to-end encrypted ML inference with Amazon SageMaker AI and FHE by Jonathan Herzog and Ruben Merz

  • From Bletchley Park to AI-Augmented Development for Encrypted Compute by David Archer

  • Check out all of the resources posted on our website here: https://fhe.org/resources/

• FHE.org Community:

  • Do you have an idea, something to share, a resource to add, or something you’d like to change about FHE.org? You can post any suggestions and proposals in the #meta channel on the FHE.org discord!

  • Interested in joining a reading group? Join the paper reading group in #reading-group. Introduce yourself there to get started!

• Don’t forget that the FHE.org website is open source and that anyone can add resources by simply opening a PR on Github: https://github.com/FHE-org/fhe-org.github.io.

💙 FHE.org is an open-source community of researchers and developers interested in Fully Homomorphic Encryption (FHE), if you’d like to contribute, join the community:

• On Discord

• On X

• On Linkedin

• On Mastodon

• On Bluesky

• On Reddit

• On the official website

👉 Think something is missing from this FHE.org digest? Help us craft the next one, join the discussion on Discord.

💻 FHE.org Software Day 2026

Planning is well underway for our upcoming Software Day, a special-edition FHE.org meetup to be held on 24th September 2026. This one-day event brings together some of the leading minds in FHE software development, with a packed programme of talks covering the latest FHE libraries and real-world applications of the technology. The day will also feature an expert Q&A panel, giving attendees the chance to put their questions directly to practitioners at the forefront of the field. Whether you’re a developer looking to get hands-on with FHE tooling or simply want to hear where the ecosystem is headed, Software Day promises to be an unmissable event. Stay tuned for more details on speakers and registration.

📅 FHE.org Conference 2027 Date Confirmed

The sixth edition of the FHE.org conference will be held in Seattle, USA, on the 4th of April 2027. This aligns as usual with Real World Crypto 2027, to be hosted by AWS and will be held immediately after FHE.org. With only 150 seats available, this is one of the most intimate gatherings in the FHE community! Keep an eye on our social media channels for further updates about tickets, program chairs for 2027, and the call for papers!

🎓 Academic Conferences

ASIACCS was held this month in Bangalore, India from 1-5 June 2026. There were several FHE-based presentations, including:

• Single-Fault Nonce Respecting Differential Attack on Hybrid Homomorphic Encryption by: Aikata Aikata (Graz University of Technology); Ahaan Dabholkar (Purdue University); Dhiman Saha (Indian Institute of Technology Bhilai); Sujoy Sinha Roy (Graz University of Technology)

• PP-Vul: Privacy-Preserving Vulnerability Detection Using Homomorphic Encryption by: Seungho Kim, Seonhye Park, Jihun Kim, Eunsoo Kim, Sanghak Oh (Sungkyunkwan University); Hyunmin Choi (NAVER Cloud); Hyoungshick Kim (Sungkyunkwan University)

• Fully Homomorphic Encryption Inference of Neural Networks Using CKKS-TFHE Scheme Switching and Accelerated Linear Layers by: Anas Banta Seutia, Muhammad Zaky Firdaus (Universitas Gadjah Mada); Muhammad Alfi Ramadhan (University of Central Florida); Kabul Kurniawan, Muhammad Husni Santriaji, Muhammad Alfian Amrizal, Reza Pulungan (Universitas Gadjah Mada); Hiroyuki Takizawa (Tohoku University)

• Towards Lightweight CKKS: On Client Cost Efficiency by Jung Hee Cheon (Seoul National University / CryptoLab Inc.); Minsik Kang (Seoul National University); Jai Hyun Park (CryptoLab Inc.)

• Fully Homomorphic Encryption Inference of Neural Networks Using CKKS-TFHE Scheme Switching and Accelerated Linear Layers by Anas Banta Seutia, Muhammad Zaky Firdaus (Universitas Gadjah Mada); Muhammad Alfi Ramadhan (University of Central Florida); Kabul Kurniawan, Muhammad Husni Santriaji, Muhammad Alfian Amrizal, Reza Pulungan (Universitas Gadjah Mada); Hiroyuki Takizawa (Tohoku University)

📰🕺 Latest Updates from the FHE.org Community

• FHE.org resources:

  • Verifiable Fully Homomorphic Encryption by Christian Knabenhans

  • End-to-end encrypted ML inference with Amazon SageMaker AI and FHE by Jonathan Herzog and Ruben Merz

• FHE.org Community:

  • Do you have an idea, something to share, a resource to add, or something you’d like to change about FHE.org? You can post any suggestions and proposals in the #meta channel on the FHE.org discord!

  • Interested in joining a reading group? Join the paper reading group in #reading-group. Introduce yourself there to get started!

• Don’t forget that the FHE.org website is open source and that anyone can add resources by simply opening a PR on Github: https://github.com/FHE-org/fhe-org.github.io.

💙 FHE.org is an open-source community of researchers and developers interested in Fully Homomorphic Encryption (FHE), if you’d like to contribute, join the community:

• On Discord

• On X

• On Linkedin

• On Mastodon

• On Bluesky

• On Farcaster

• On Reddit

• On the official website

👉 Think something is missing from this FHE.org digest? Help us craft the next one, join the discussion on Discord.

🎓 Academic Conferences

Eurocrypt was held in Rome, Italy, this month and there were several FHE-based works presented.

• REFHE: Fully homomorphic ALU by Zvika Brakerski, Offir Friedman, Daniel Golan, Alon Gurny, Dolev Mutzari, and Ohad Sheinfeld

• HERDS: Multi-Key Fully Homomorphic Encryption with Sublinear Bootstrapping by

  Binwu Xiang, Seonhong Min, Intak Hwang, Zhiwei Wang, Haoqi He, Yuanju Wei, Kang Yang, Jiang Zhang, Yi Deng, and Yu Yu

• Improved Radix-based Approximate Homomorphic Encryption for Large Integers via Lightweight Bootstrapped Digit Carry by Gyeongwon Cha, Dongjin Park, and Joon-Woo Lee

• Fully Asymmetric Anamorphic Homomorphic Encryption from LWE by Amit Deo and Benoît Libert

There was also an afterwork event at Eurocrypt, hosted by Zama, and there were two talks of interest.

• Zama’s Confidential Smart Contracts Protocol by Morten Dahl (slides below).

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• Zama’s Year in Research by Nigel Smart (slides below).

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7.12MB ∙ PDF file

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Public Key Cryptography (PKC 2026) was held in West Palm Beach, USA, and there were two FHE papers presented.

• Succinctly Verifiable Computation over Additively-Homomorphically Encrypted Data: Making Privacy-Preserving Blueprints Practical by Scott Griffy, Markulf Kohlweiss, Anna Lysyanskaya, and Meghna Sengupta

• Faster Bootstrapping for CKKS with Less Modulus Consumption by

  Lianglin Yan, Pengfei Zeng, Heyang Cao, Peizhe Song, and Mingsheng Wang

📰🕺 Latest Updates from the FHE.org Community

• Previous Meetups and Meet the Community interviews you may have missed:

  • Low Communication Threshold FHE from Standard (Module-)LWE w/ Hiroki Okada

  • Efficient Homomorphic Matrix Computation for Secure Transformer Inference w/ Miran Kim

  • FHE in Production w/ Rotem Tsabary

  • Evaluating Larger Lookup Tables using CKKS w/ Jules Dumezy

  • Failure Probability in FHE Measured with Rare Event Simulation w/ Mathieu Ballandras

  • Meet the Community w/ Miran Kim

• Presentations from FHE.org 2026 in Taipei you may have missed:

  • Practical Zero-Knowledge PIOP for Maliciously Secure Multiparty Homomorphic Encryption w/ Intak Hwang

  • Batch, Pack, and Prove: More Efficient Verifiable Computation for CKKS w/ Antonio Guimarães

  • To Search and Protect: An MPC/FHE Approach to Encrypted Search w/ Shai Halevi

  • GG-GSW: Chosen-Ciphertext Secure Leveled FHE From Gadget Trapdoors w/ Jérôme Nguyen

  • Fully Homomorphic Encryption for Matrix Arithmetic w/ Yongwoo Lee

  • HEaaN2, a High-Performance CKKS Library w/ Seonghak Kim

  • Why It Still Makes Sense to Talk About Average-Case Noise Analysis in FHE: The BGV Example w/ Matilda Urani

  • Randomization in FHE and TFHE w/ Nigel Smart

  • Accelerating TFHE with Sorted Bootstrapping Techniques w/ Loris Bergerat

  • Scaling up Privacy-Preserving ML: a CKKS Implementation of LLaMA-2-7B w/ Jaiyoung Park

  • Iterated Hash Functions over Encrypted Data: News from the Front w/ Marc Joye

• FHE.org resources:

  • DPHE: Protecting Server Privacy in CKKS-based Protocols by Jinyeong Seo

  • Tutorial: Accelerating Private Cloud Computing with FIDESlib by Carlos Agulló-Domingo, Óscar Vera-López, and José L. Abellán

  • Exploring Fully Homomorphic Encryption by Vitalik Buterin

  • Guide to Applications of Homomorphic Encryption by Miran Kim

  • Efficient Homomorphic Integer Computer from CKKS by Jaehyung Kim

  • Security Notions Zoo: A taxonomy site for cryptography security notions for FHE by Jules Dumezy and Marc Renard

  • A Decade (or so) of fully homomorphic encryption by Craig Gentry

  • Beyond Zero Knowledge: How Fully Homomorphic Encryption Enables Private Shared State by Samuel Wong

  • Bivariate CKKS by Jules Dumezy
    

• FHE.org Community:

  • Do you have an idea, something to share, a resource to add, or something you’d like to change about FHE.org? You can post any suggestions and proposals in the #meta channel on the FHE.org discord!

  • Interested in joining a reading group? Join the paper reading group in #reading-group. Introduce yourself there to get started!

• Don’t forget that the FHE.org website is open source and that anyone can add resources by simply opening a PR on Github: https://github.com/FHE-org/fhe-org.github.io.

💙 FHE.org is an open-source community of researchers and developers interested in Fully Homomorphic Encryption (FHE), if you’d like to contribute, join the community:

• On Discord

• On X

• On Linkedin

• On Mastodon

• On Bluesky

• On Farcaster

• On Reddit

• On the official website

👉 Think something is missing from this FHE.org digest? Help us craft the next one, join the discussion on Discord.

This meetup features Mathieu Ballandras, a researcher at Zama focusing on TFHE, presenting Failure Probability in FHE Measured with Rare Event Simulation.

For more information and link to RSVP, see the event luma page at https://luma.com/FHE.org-087.

Abstract

The security of homomorphic encryption schemes based on the Learning With Errors problem requires the presence of a noise term in ciphertext. This noise can grow during homomorphic operations and can lead to decryption failure. The probability of such an event is called the failure probability.

In the IND-CPA-D security model, failures are not only an inconvenience but also a security issue as they leak information about the secret key. It is therefore essential to enforce low failure probabilities.

​In TFHE, these probabilities are usually predicted theoretically by assuming the noise follows a Gaussian distribution.

We use a technique of rare event simulation called importance splitting to experimentally measure the failure probability. We obtain strong experimental guarantees that for several standard variants of TFHE, the usual Gaussian model for noise is conservative and that a refined model based on Irwin--Hall distribution is valid.

​These experiments confirm the IND-CPA-D security of the scheme.

About the speaker

Mathieu Ballandras is a researcher at Zama, his research focuses on TFHE.

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Join the discord server to discuss FHE related topics with the community: discord.fhe.org.

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The FHE.org team

🇹🇼 FHE.org 2026 Taipei Conference

A heartfelt thank you to everyone in the FHE community for coming together and making this year our 5th successful annual conference with 55 submissions, 10 accepted talks, 23 accepted posters, 1 invited speaker, 168 registered attendees, and 25 sponsors (including Apple)!

We’ve made all video resources from the conference available at fhe.org/2026/resources/. Remember that anyone can add their resources to the FHE.org github repository!

See a program view of all resources here, or if you prefer to just watch the presentations back to back, here is the FHE.org 2026 Taipei Conference playlist on Youtube. These presentations are also outlined below.

🎤 Fully Homomorphic Encryption for Matrix Arithmetic

Yongwoo Lee from DESILO and Inha University presents "Fully Homomorphic Encryption for Matrix Arithmetic".

See the video on Youtube here.

🎤 GG-GSW: Chosen-Ciphertext Secure Leveled FHE From Gadget Trapdoors

Jérôme Nguyen from Universität der Bundeswehr Munich presents "GG-GSW: Chosen-Ciphertext Secure Leveled FHE From Gadget Trapdoors".

See the video on Youtube here.

🎤 Why It Still Makes Sense to Talk About Average-Case Noise Analysis in FHE: The BGV Example

Matilda Urani from Politecnico di Torino presents "Why It Still Makes Sense to Talk About Average-Case Noise Analysis in FHE: The BGV Example".

See the video on Youtube here.

🎤 Scaling up Privacy-Preserving ML: a CKKS Implementation of LLaMA-2-7B

Jaiyoung Park from Seoul National University and CryptoLab Inc presents "Scaling up Privacy-Preserving ML: a CKKS Implementation of LLaMA-2-7B".

See the video on Youtube here.

🎤 HEaaN2, a High-Performance CKKS Library

Seonghak Kim on behalf of CryptoLab Inc presents "HEaaN2, a High-Performance CKKS Library".

See the video on Youtube here.

🎤 Accelerating TFHE with Sorted Bootstrapping Techniques

Loris Bergerat from Zama and Université Caen Normandie presents "Accelerating TFHE with Sorted Bootstrapping Techniques".

See the video on Youtube here.

🎤 Randomization in FHE and TFHE

Nigel Smart from Zama and KU Leuven presents "Randomization in FHE and TFHE".

See the video on Youtube here.

🎤 Iterated Hash Functions over Encrypted Data: News from the Front

Marc Joye from Zama presents "Iterated Hash Functions over Encrypted Data: News from the Front".

See the video on Youtube here.

🎤 Batch, Pack, and Prove: More Efficient Verifiable Computation for CKKS

Antonio Guimarães from IMDEA Software Institute presents "Batch, Pack, and Prove: More Efficient Verifiable Computation for CKKS".

See the video on Youtube here.

🎤 Practical Zero-Knowledge PIOP for Maliciously Secure Multiparty Homomorphic Encryption

Intak Hwang from Seoul National University presents "Practical Zero-Knowledge PIOP for Maliciously Secure Multiparty Homomorphic Encryption".

See the video on Youtube here.

🎤 Invited Talk: To Search and Protect: An MPC/FHE Approach to Encrypted Search

Shai Halevi from AWS, presents an invited talk "To Search and Protect: An MPC/FHE Approach to Encrypted Search".

See the video on Youtube here.

🪧 Posters from This Year’s Conference

See the full list of resources from each poster presenter on fhe.org/2026/resources.

• Evaluating Larger Lookup Tables using CKKS — Jules Dumezy, Andreea Alexandru, Yuriy Polyakov, Pierre-Emmanuel Clet, Olive Chakraborty and Aymen Boudguiga

• Complex Elections via Threshold (Fully) Homomorphic Encryption — Charlotte Bonte, Georgio Nicolas and Nigel Smart

• Peregrine: One-Shot Fine-Tuning for FHE Inference of General Deep CNNs — Huaming Ling, Ying Wang and Si Chen

• Fheanor: a new, modular FHE library for designing and optimising schemes — Hiroki Okada, Rachel Player and Simon Pohmann

• From Leuven with Love: An overview of arithmetic advances in the TFHE space — Jan-Pieter D’Anvers, Thomas de Ruijter, and Michiel Van Beirendonck

• Achieving 128-bits of Security on the Optalysys Accelerator for TFHE — Erin Hales, Thanh-Huyen Nguyen, Emmet Friel and Florent Michel

• Sub-Millisecond TFHE Bootstrapping on GPU — Pedro Geraldo M. R. Alves, Beka Barbakadze, Enzo Di Maria, Jakub Klemsa, Agnes Leroy and Guillermo Oyarzun

• Better GBFV Bootstrapping and Faster Encrypted Edit Distance Computation — Robin Geelen and Frederik Vercauteren

• The First FPGA Backend for the HEIR Compiler: Evaluating Boolean vs. Arithmetic Pipelines for Practical FHE Acceleration — Wouter Legiest, Thomas de Ruijter, Asra Ali, Jeremy Kun and Ingrid Verbauwhede

• YATA: Yet Another TFHE Accelerator with Key Compression and Radix-8 NTT — Kotaro Matsuoka and Takashi Sato

• Practical SNARGs for Matrix Multiplications over Encrypted Data — Michael Walter, Louis Tremblay Thibault and Jiapeng Zhang

• HE-based On-the-Fly MPC, Revisited: Universal Composability, Approximate and Imperfect Computation, Circuit Privacy — Ganyuan Cao, Sylvain Chatel and Christian Knabenhans

• Veil: A Fully Homomorphic Encryption Framework for Privacy-Preserving Machine Learning — Abdelrahaman Aly, Chiara Marcolla, Victor Mateu, Pradeep Mishra, Aryan Raj, Sergi Rovira, Victor Sucasas, Luis Zamarripa and Floyd Zweydinger

• Concrete Estimation of Correctness and IND-CPA-D Security for FHE via Rare Event Simulation — Mathieu Ballandras, Jean-Baptiste Orfila and Samuel Tap

• A New Benchmarking Suite for FHE — Andreea Alexandru, Flavio Bergamaschi, Shruthi Gorantala and Shai Halevi

• Provably Secure Approximate Computation Protocols from CKKS — Intak Hwang, Yisol Hwang, Miran Kim, Dongwon Lee and Yongsoo Song

• A White-Box Bootstrapping Approach for High Precision Comparison Over Homomorphic Encryption — Deokhwa Hong, Heesoo Lee, Young-Sik Kim and Yongwoo Lee

• Pirouette: Query Efficient Single-Server PIR — Jiayi Kang and Leonard Schild

• FastFFN: Low-Latency Feedforward Block Evaluation for Secure Transformer Inference — Linru Zhang, Xiangning Wang, Xianhui Lu, Huaxiong Wang, Adhiraj Saxena and Kwok Yan Lam

• HEIR: Fully Homomorphic Machine Learning with a Universal Compiler — Asra Ali and Jeremy Kun

• Faster Homomorphic Evaluation of SHA3 — Tim Seuré and Elias Suvanto

• Let’s Talk: How TFHE Became Practical — Pierre Gardrat, Agnès Leroy, Arthur Meyre, Jean-Baptiste Orfila and Samuel Tap

• Efficient Private Embedding Lookup via Independent Vector Evaluation — Daehyun Jang, Jaehee Kang, Hanee Rhee and Jung Hee Cheon

🤝 Sponsors

A sincere thank you to all our sponsors this year for making this conference a success and allowing so many students to attend! If you’d like to become a sponsor for the next conference, reach out at contact@fhe.org.

See the full list of recent sponsors on fhe.org/sponsor.

📅 Upcoming Events

Stay tuned for more news about the upcoming meetups and our second online major event: FHE.org Software Day.

FHE.org is an open-source community of researchers and developers interested in Fully Homomorphic Encryption (FHE), if you’d like to contribute, join the community:

• Twitter / X - @fhe_org

• Reddit - /r/fhe

• Mastodon - @fhe@ioc.exchange

• Linkedin - fhe-org

• Bluesky - @fheorg.bsky.social

This meetup features Jules Dumezy, a PhD candidate at CEA-List and Université Paris-Saclay, France, presenting Evaluating Larger Lookup Tables using CKKS.

For more information and link to RSVP, see the event luma page at https://luma.com/FHE.org-086.

Abstract

​This presentation will introduce two novel algorithms for functional bootstrapping in CKKS: Binary Multiplexer Tree (BMT-FBT) and Collapsed Multiplexer Tree (CMT-FBT). While standard CKKS functional bootstrapping struggles with efficiency for larger Lookup Tables (LUTs), these new methods leverage ciphertext bit and digit decompositions to overcome these limitations. The talk will demonstrate how these techniques allow for the practical evaluation of LUTs up to 20+ bits.

About the speaker

Jules Dumezy is a PhD candidate at CEA-List and Université Paris-Saclay, France. He holds an Engineering Degree in Embedded and Cyber-Physical Systems from Centrale Lille. His research focuses on applied cryptography and privacy-preserving technologies, specifically on general improvements for the CKKS scheme and enabling more efficient computations for FHE.

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Join the discord server to discuss FHE related topics with the community: discord.fhe.org.

See you soon!

The FHE.org team

• Conference attendees will check-in on arrival and get a badge with their lu.ma provided information on it. If you’d like to change the information displayed on your badge, please let us know!
  

• At registration, attendees also receive this year’s special collector goodie. In a previous year at Toronto’s conference, attendees received an adorable Canadian themed gift of a plushie beaver (or BeFHEr, if you will).

  

  HINT: This year’s goodie is a surprise, but here’s a hint — once it’s gone, it’s BEARY GONE.

• At check-in, you’ll be able to grab a morning snack, beverage of choice, and mingle with some of the leading researchers in the FHE space, including research and development leaders from major FHE libraries and schemes.
  

  

  The FHE.org community comes from all around the world to meet in person, discuss research, present on topics, and meet future collaborators and employers. Before and after the conference, you can also meet the same community (over 5,000 users) on our FHE.org discord at https://discord.fhe.org.
  

• At the conference, there are both stage presentations and poster presentations.

  • Stage presentations are done with slides and a speaker on stage to the audience, with a succinct Q&A.
    

    

  • Poster presentations allow for a more intimate discussion and 1:1 Q&A with the authors who make themselves available at the poster session and during breaks throughout the day.
    

    

  • Attendees enjoy talks from some of the most prolific figures in the FHE (and cryptography!) space. For this year, the conference Program Chairs announced the invited speaker as Shai Halevi, another legend of the FHE space.

    

• Between talks and poster sessions are snack breaks, a specially catered buffet lunch, and our famous DJed after party with drinks, food, and a photo booth for those who want to remember the occasion for their existing teams or new acquaintances!

  

• The conference is a full day packed with interesting and carefully selected talks from the community. You can see the full program here at https://fhe.org/2026/program.
  

• This year the conference has gotten even more interest from across the world as we welcome 25 generous sponsors that have enabled us to waive student costs and provide the highest quality and best attended conference in the FHE space.
  
  It’s worth thanking all our sponsors (especially our repeat sponsors from previous years!), including our most recent addition to the sponsor list — Apple!

Want to join us at the 5th Annual FHE.org Conference on Fully Homomorphic Encryption, colocated with Real World Crypto 2026 in Taipei, Taiwan, on March 8, 2026?

As with last year, students can register for free by emailing contact@fhe.org from their academic email address.

Sponsors can also participate still by emailing with their proposals!

This year there will only be 200 seats available, so reserve them early!

Get your tickets now

💙 FHE.org is an open-source community of researchers and developers interested in Fully Homomorphic Encryption (FHE), if you’d like to contribute, join the community:

• On Discord

• On Twitter

• On Linkedin

• On Mastodon

• On the official website

This meetup features Dr. Rotem Tsabary, founder and CEO of Lattica, presenting FHE in Production.

For more information and link to RSVP, see the event luma page at https://luma.com/FHE.org-085.

Abstract

​Fully Homomorphic Encryption (FHE) has long promised the ability to compute on encrypted data, but real-world deployment has been limited by performance, usability, and system integration challenges.

​This talk presents a production-oriented view of FHE, focusing on what changes when encrypted computation is treated as a systems and execution problem rather than a purely cryptographic one. It introduces a GPU-native approach to FHE, where ciphertexts are represented as tensors and homomorphic operations are expressed as batched, parallel programs that map directly to modern accelerators.

​The presentation covers the architectural principles behind this approach and includes a practical example of how FHE programs are written and executed on a GPU, from ciphertext layout to custom kernel execution. The goal is to give practitioners an intuitive understanding of what “programming FHE for acceleration hardware” looks like in practice.

About the speaker

Dr. Rotem Tsabary is a cryptographer and systems engineer, and the founder and CEO of Lattica. She holds a PhD in cryptography from the Weizmann Institute of Science and has prior experience utilizing large-scale ML infrastructure at Google. Her current work focuses on re-architecting Fully Homomorphic Encryption as a GPU-accelerated, tensorized compute workload suitable for deployment in real production systems.

Don’t miss the conference

The 5th Annual FHE.org Conference, co-located with Real World Crypto 2026, takes place in cooperation with IACR (ICW-IACR) and will be held at the Taipei Marriott Hotel in Taipei, Taiwan on Sunday, March 8, 2026.

You won't want to miss this year's presentations, from 55 submissions (10 talks and 23 posters accepted) and invited speaker Shai Halevi presenting "To Search and Protect: An MPC/FHE Approach to Encrypted Search".

Make sure you’ve RSVPed early and we’ll see you there!

Never miss an update

Join the discord server to discuss FHE related topics with the community: discord.fhe.org.

See you soon!

The FHE.org team

This meetup features Miran Kim, associate professor of the Department of Mathematics and affiliated with the Department of Computer Science at Hanyang University, presenting Efficient Homomorphic Matrix Computation for Secure Transformer Inference.

For more information and link to RSVP, see the event luma page at https://luma.com/FHE.org-084.

Abstract

Homomorphic encryption (HE) enables computation directly on encrypted data without requiring decryption, thereby preserving data confidentiality. This talk introduces a new diagonal-encoding–based method for homomorphic matrix multiplication. Building on this technique, I present THOR, a secure transformer inference framework that designs core transformer operations to achieve both high efficiency and numerical stability in the encrypted domain. I conclude by presenting comprehensive benchmark results that demonstrate practical end-to-end secure inference for transformer models on encrypted data, highlighting significant performance improvements over prior HE-based approaches.

About the speaker

Miran Kim is an associate professor of the Department of Mathematics and affiliated with the Department of Computer Science at Hanyang University. She received her Ph.D. in mathematical sciences from Seoul National University, Korea, in 2017. Her research focuses on the design of novel strategies for secure and privacy-preserving data analysis using homomorphic encryption. She has extensive experience in the algorithmic optimization of homomorphic encryption, as well as in the design and implementation of efficient protocols for data query processing, genomic data analysis, and machine learning.

Never miss an update

Join the discord server to discuss FHE related topics with the community: discord.fhe.org.

See you soon!

The FHE.org team

🇹🇼 FHE.org Taipei 2026 Conference

A reminder to our community to join us at the 5th Annual FHE.org Conference on Fully Homomorphic Encryption, colocated with Real World Crypto 2026 in Taipei, Taiwan, on March 8, 2026. It’s also conveniently located at the Taipei Marriott Hotel where the Real World Crypto 2026 main conference will be held from March 9th!

As with last year, students can register for free by emailing contact@fhe.org from their academic email address.

This year there will only be 200 seats available, so reserve them early!

➡️ Get your tickets now

🎓 Upcoming FHE.org Meetups and Related Events

• Hiroki Okada, a researcher at KDDI Research in Japan, will present his work on Low Communication Threshold FHE next Thursday. Be sure to sign up here.

• The 9th HomomorphicEncryption.org Standards Meeting will be held in Seoul, Korea, on March 5th and 6th, 2026. Find out more information on their event website.

📰🕺 Latest Updates from the FHE.org Community

• FHE.org resources:

  • “Fully Homomorphic Encryption” by Prof. Nigel Smart, KU Leuven

  • “Introduction to Homomorphic Encryption” by Jean-Sébastien Coron, University of Luxembourg

  • “OpenFHE AAAI 2024 Tutorial: Fully Homomorphic Encryption for Privacy-Preserving Machine Learning Using the OpenFHE Library” by Ian Quah, Ph.D. student at the University of Washington’s Ahmed Lab, Yuriy Polyakov, Vice President of Cryptography and a Principal Scientist at Duality Technologies, and Sukanya, a Research Engineer and Tech Lead.

  • “The State of FHE report #2: Hardware Edition” by Zama

• FHE.org Community:

  • Do you have an idea, something to share, a resource to add, or something you’d like to change about FHE.org? You can post any suggestions and proposals in the #meta channel on the FHE.org discord!

  • Interested in joining a reading group? Join the paper reading group in #reading-group. Introduce yourself there to get started!

• Don’t forget that the FHE.org website is open source and that anyone can add resources by simply opening a PR on Github: https://github.com/FHE-org/fhe-org.github.io.

💙 FHE.org is an open-source community of researchers and developers interested in Fully Homomorphic Encryption (FHE), if you’d like to contribute, join the community:

• On Discord

• On X

• On Linkedin

• On Mastodon

• On Bluesky

• On Farcaster

• On Reddit

• On the official website

👉 Think something is missing from this FHE.org digest? Help us craft the next one, join the discussion on Discord.

This meetup features Hiroki Okada, researcher at KDDI Research, presenting Low Communication Threshold FHE from Standard (Module-)LWE.

For more information and link to RSVP, see the event luma page at https://luma.com/FHE.org-083.

Abstract

Threshold fully homomorphic encryption (ThFHE) is a multi-party extension of FHE; any subset of at least T out of N parties can decrypt the ciphertexts by combining their decryption shares. Recently, Passelègue and Stehlé (Asiacrypt 2024) presented a ThFHE scheme with polynomially short decryption shares from the “known-norm” variant of learning with errors (LWE) assumption, in which the norm of the secret key is leaked to the adversary. While known-norm LWE is reduced from standard LWE, its module extension, known-covariance module-LWE (MLWE), lacks a known reduction from standard MLWE. Hence, extending their ThFHE scheme to the MLWE-based construction remains an open question.

In this paper, we address this open problem: We construct a ThFHE scheme with polynomially small decryption shares from standard LWE/MLWE. Our core technique, which we call noise padding, eliminates the need of known-norm variants of LWE. We distribute shares of a padding noise and use them to adjust the distribution of decryption noise so that no information about the secret key is leaked. Furthermore, our ThFHE efficiently realizes arbitrary T-out-of-N threshold decryption via simple Shamir secret sharing instead of {0,1}-linear secret sharing. Hence, the sizes of the keys, ciphertexts and decryption shares in our scheme are compact: they are O(1) w.r.t. the number of parties N.

About the speaker

Hiroki Okada is a researcher at KDDI Research.

His research interests include lattice-based cryptography and especially FHE.

Platform Note

We’ve recently switched from using Zoom for our meetups to Google Meet. The meetup link will remain the same (https://fhe.org/meetups/join). If you have any issues getting into the new meetup, please email us at contact@fhe.org.

Never miss an update

Join the discord server to discuss FHE related topics with the community: discord.fhe.org.

See you soon!

The FHE.org team

The FHE.org 2026 program chairs have announced that Shai Halevi, Senior Principal Applied Scientist at AWS Cryptography, and fellow of the IACR, will give the invited talk at FHE.org 2026.

Be sure not to miss this great talk!

2026 Conference Program

The FHE.org 2026 program chairs have finalized the program for the 5th annual FHE.org conference this March 8th in Taipei, Taiwan.

Check out all the great planned talks and posters for this year, and be sure to join us for our yearly afterparty!

The program committee also accepted 23 posters this year:

• Peregrine: One-Shot Fine-Tuning for FHE Inference of General Deep CNNs

• Fheanor: a new, modular FHE library for designing and optimising schemes

• From Leuven with Love: An overview of arithmetic advances in the TFHE space

• Achieving 128-bits of Security on the Optalysys Accelerator for TFHE

• Sub-Millisecond TFHE Bootstrapping on GPU

• Better GBFV Bootstrapping and Faster Encrypted Edit Distance Computation

• The First FPGA Backend for the HEIR Compiler: Evaluating Boolean vs. Arithmetic Pipelines for Practical FHE Acceleration

• YATA: Yet Another TFHE Accelerator with Key Compression and Radix-8 NTT

• Practical SNARGs for Matrix Multiplications over Encrypted Data

• HE-based On-the-Fly MPC, Revisited: Universal Composability, Approximate and Imperfect Computation, Circuit Privacy

• Veil: A Fully Homomorphic Encryption Framework for Privacy-Preserving Machine Learning

• Concrete Estimation of Correctness and IND-CPA-D Security for FHE via Rare Event Simulation

• A New Benchmarking Suite for FHE

• Provably Secure Approximate Computation Protocols from CKKS

• A White-Box Bootstrapping Approach for High Precision Comparison Over Homomorphic Encryption

• Pirouette: Query Efficient Single-Server PIR

• FastFFN: Low-Latency Feedforward Block Evaluation for Secure Transformer Inference

• HEIR: Fully Homomorphic Machine Learning with a Universal Compiler

• Faster Homomorphic Evaluation of SHA3

• Let’s Talk: How TFHE Became Practical

• Efficient Encrypted Embedding Lookup via Independent Vector Evaluation

For full details, check out our online program here: https://fhe.org/2026/program.

Register for the Conference

Make sure you’ve registered for your tickets!

If you’re a student make sure to reach out to contact@fhe.org from your academic email address to request waiving the registration fee.

Want to know what to expect on the day? Check out our guide on the conference website: https://fhe.org/2026

Never miss an update

Join the discord server to discuss FHE related topics with the community: discord.fhe.org.

See you soon!

The FHE.org team

The 2025 one-year review from FHE.org is here!

We are celebrating another remarkable year of advancements for the FHE space, thanks to you! 🫵

🇹🇼 FHE.org Taipei 2026 Conference

A reminder to our community to join us at the 5th Annual FHE.org Conference on Fully Homomorphic Encryption, colocated with Real World Crypto 2026 in Taipei, Taiwan, on March 8, 2026. It’s also conveniently located at the Taipei Marriott Hotel where the Real World Crypto 2026 main conference will be held from March 9th!

As with last year, students can register for free by emailing contact@fhe.org from their academic email address.

This year there will only be 200 seats available, so reserve them early!

Accepted presentations will be announced on December 19th, 2025.

➡️ Get your tickets now

🎓 Academic Conferences

Asiacrypt was held in Melbourne, Australia, this month — and there were several works presented on FHE, including:

• Low Communication Threshold FHE from Standard (Module-)LWE by Hiroki Okada and Tsuyoshi Takagi

• Bootstrapping (T)FHE Ciphertexts via Automorphisms: Closing the Gap Between Binary and Gaussian Keys by Olivier Bernard and Marc Joye

• PaCo: Bootstrapping for CKKS via Partial CoeffToSlot by Jean-Sébastien Coron and Tim Seuré

• Accelerating TFHE with Sorted Bootstrapping Techniques by Loris Bergerat, Jean-Baptiste Orfila, Samuel Tap, and Adeline Roux-Langlois

• Practical Dense-Key Bootstrapping with Subring Secret Encapsulation by

  Shihe Ma, Tairong Huang, Anyu Wang, and Xiaoyun Wang

• Carousel: Fully Homomorphic Encryption with Bootstrapping over Automorphism Group by Intak Hwang, Seonhong Min, and Yongsoo Song

• PriFHEte: Achieving Full-Privacy in Account-based Cryptocurrencies is Possible

  by Varun Madathil and Alessandra Scafuro

• Bootstrappable Fully Homomorphic Attribute-Based Encryption with Unbounded Circuit Depth by Feixiang Zhao, Shixin Chen, Man Ho Au, Jian Weng, Huaxiong Wang, and Jian Guo

• IND-CPA-D and KR-D Security with Reduced Noise from the HintLWE Problem by

  Tabitha Ogilvie

• On the Security and Privacy of CKKS-based Homomorphic Evaluation Protocols by Intak Hwang, Seonhong Min, Jinyeong Seo, and Yongsoo Song

• Cryptanalysis on Lightweight Verifiable Homomorphic Encryption by

  Daehyun Jang and Jung Hee Cheon

Keep an eye out at the start of next year, as some of these papers will be presented at FHE.org meetups!

📰🕺 Latest Updates from the FHE.org Community

• Previous Meetups and Meet the Community interviews you may have missed:

  • Proving Correct Execution of TFHE’s Bootstrapping using plonky2 w/ Louis Tremblay Thibault

  • FHE for Multiple Parties using NTRU and LWE w/ Oliver Zajonc

  • Meet the Community w/ Oliver Zajonc

  • Meet the Community w/ Louis Tremblay Thibault

• FHE.org Resources:

  • “Speedrunning TFHE-rs” by David Wong, Founder of zkSecurity

  • “Fully Homomorphic Encryption, 10 Years Later: Definitions and Open Problems” by Daniele Micciancio, professor in the Computer Science & Engineering department at the University of California, San Diego

  • “Cryptography Bootcamp: Homomorphic Encryption (Part 1, SWHE)” by Shai Halevi, IBM T.J. Watson Research Center

• “Winter School on Cryptography: Fully Homomorphic Encryption” by Craig Gentry

• “Low Communication Threshold Fully Homomorphic Encryption” by Alain Passelègue

• “Bootstrapping Discrete Data with CKKS” by Jaehyung Kim, Stanford University

• FHE.org Community:

  • Do you have an idea, something to share, a resource to add, or something you’d like to change about FHE.org? You can post any suggestions and proposals in the #meta channel on the FHE.org discord!

  • Interested in joining a reading group? Join the paper reading group in #reading-group. Introduce yourself there to get started!

• Don’t forget that the FHE.org website is open source and that anyone can add resources by simply opening a PR on Github: https://github.com/FHE-org/fhe-org.github.io.

💙 FHE.org is an open-source community of researchers and developers interested in Fully Homomorphic Encryption (FHE), if you’d like to contribute, join the community:

• On Discord

• On X

• On Linkedin

• On Mastodon

• On Bluesky

• On Farcaster

• On Reddit

• On the official website

👉 Think something is missing from this FHE.org digest? Help us craft the next one, join the discussion on Discord.

🇦🇷 FHE at DevConnect

The first series of presentations was at the CoFHE shop from Zama at Devconnect in Buenos Aires:

• Fireside chat with ‪Figment w/ Sthefano Batista

• Deep dive into ERC-7984 w/ Thomas Binetruy (Zaïffer) and Eric DeCourcy ‪(OpenZeppelin‬)

• Hardware accelerated FHE in practice w/ ‪Nic Lawrence (Optalysys‬)

• Intro to the Confidential Token Association w/ Remi Gai ‪(Inco Network)

• Inside the confidential token standard w/ ‪Aryeh Greenberg (OpenZeppelin‬)

• Building FHE consumer apps with Deberry’s & PlayAscend w/ Thomas Belloc (Zcorp)

• Confidential onchain finance coffee with Zaïffer and TokenOps w/ Bilal El Alamy (Zaïffer) and Fabio Mancini (TokenOps)

• Fireside chat on privacy with Juan Benet w/ Kyle O’Brien (Zama) and Juan Benet (Protocol Labs)

• Interoperability and confidentiality with Layer Zero w/ Matt Krak (LayerZero)

• Benchmarking the future of private computations with P2P.org w/ Konstantin Ivanov (P2P Labs)

• Confidential transactions on Ethereum with Zama w/ Aurora Poppyseed (Zama)

• Confidential smart contracts usingthe Zama Protocol w/ Clément Danjou (Zama)

• GovTech, privacy, and the future of digital nations with Onchain City w/ Kimberly Adams

The second series of presentations was a mixture of presentations and panels at the Nogal Room (Red Pavilion) at Devconnect in Buenos Aires:

• DBFV - A new FHE Scheme w/ Fhenix

• FHEthereum for Trustless Ethereum w/ Eugene Joo (Crypto Lab)

• Deploying FHE in Permissionless System: Building the Application Layer and Beyond w/ Gurgen Arakelov (FairMath)

• Lessons from ZKPs for FHE w/ Miha Stopar (Ethereum Foundation)

• Phantom w/ Janmajaya Mall (phantom.zone)

• Building with FHE: Practical Examples and Lessons Learned w/ Alessandro Cara (Enclave)

• Practical Challenges and Opportunities for FHE in Ethereum w/ Nam, Keewoo, Tom (FHEnix), Clément Danjou (Zama) , Gurgen Arakelov (FairMath)

Additionally, resources from Encryption Day by Fhenix at Devconnect in Buenos Aires are expected to be made available online soon.

🎤 Academic Conferences

The FHE.org submission deadline closed in November, and we received 55 submissions for the 2026 edition of the conference. We thank everyone who sent a submission. Decisions will be sent to all submitters on December 19th, 2025!

In November, the 20th International Workshop on Security (IWSEC) was held in Fukuoka, Japan. There was a works on FHE:

• Approximate CRT-Based Gadget Decomposition for Fully Homomorphic Encryption by: Olivier Bernard and Marc Joye

There were also two FHE-based invited talks on the conferences circuit in the past few months:

• Professor Yongsoo Song gave an invited talk on Lattice-based Proof Systems and Application to Homomorphic Encryption at the 28th Annual International Conference on Information Security and Cryptology, held in Korea.

• Professor Nigel Smart gave an invited talk on Cloud Encryption and Blockchain: a primer on TFHE and FHEVM at Financial Cryptography in Rome 2025, held in Italy.

🎤 Upcoming Meetups

Don’t miss the next meetup coming next Thursday, FHE for Multiple Parties using NTRU and LWE w/ Oliver Zajonc.

Couldn’t make it to a previous meetup? Check the meetups page on FHE.org for recordings and resources from all previous meetups.

Make sure you’re subscribed to this digest to get notifications of all future FHE.org Meetups as they are scheduled.

Got a paper or presentation you think the community might be interested in or would make a good meetup? Get in touch at contact@fhe.org.

📰🕺 Latest Updates from the FHE.org Community

• Previous Meetups and Meet the Community interviews you may have missed:

  • Accelerating NTT with RISC-V Vector Extension for Fully Homomorphic Encryption w/ Alexandre Rodrigues

  • Meet the Community w/ Shane Kosieradzki

  • Meet the Community w/ Hannah Mahon

  • Meet the Community w/ Alexandre Rodrigues

• FHE.org Community:

  • Do you have an idea, something to share, a resource to add, or something you’d like to change about FHE.org? You can post any suggestions and proposals in the #meta channel on the FHE.org discord!

  • Interested in joining a reading group? Join the paper reading group in #reading-group. Introduce yourself there to get started!

• Don’t forget that the FHE.org website is open source and that anyone can add resources by simply opening a PR on Github: https://github.com/FHE-org/fhe-org.github.io.

💙 FHE.org is an open-source community of researchers and developers interested in Fully Homomorphic Encryption (FHE), if you’d like to contribute, join the community:

• On Discord

• On X

• On Linkedin

• On Mastodon

• On Bluesky

• On Farcaster

• On Reddit

• On the official website

👉 You think something is missing from this FHE.org digest? Help us craft the next one, join the discussion on Discord.

This meetup features Oliver Zajonc, PhD Candidate at COSIC, KU Leuven, presenting FHE for Multiple Parties using NTRU and LWE.

For more information and link to RSVP, see the event luma page at https://luma.com/FHE.org-082.

Abstract

When using FHE in the setting with multiple parties, a major consideration is key management. There are two main paths, either each party keeps their own key, called multikey FHE (MKFHE), or the parties use some key agreement procedure, often MPC, to agree on some common key, which can then be used as if this were the single key setting, called multiparty FHE (MPFHE). The first such work was based on the NTRU problem, which brought with it some major benefits in both efficiency and key size. It was later found to be insecure due to using overstretched parameters, after which nearly all work in FHE for all settings has been based on LWE.

​Recently, NTRU-based FHE has made a return due to FINAL. In this work, we expand FINAL to both the MKFHE and MPFHE settings, bringing the efficiency and key size benefits of NTRU to multiple parties, without using overstretched parameters.

About the speaker

Oliver is a PhD Candidate at COSIC, KU Leuven. After completing his Master’s in Mathematics at KU Leuven, he’s published works on FHE, Garbled Circuits, and Secret Sharing-based MPC.

Platform Note

We’ve recently switched from using Zoom for our meetups to Google Meet. The meetup link will remain the same (https://fhe.org/meetups/join). If you have any issues getting into the new meetup, please email us at contact@fhe.org.

Never miss an update

Join the discord server to discuss FHE related topics with the community: discord.fhe.org.

See you soon!

The FHE.org team

This meetup features Louis Tremblay Thibault, Cryptography researcher at Zama and PhD student at ÉTS Montréal, presenting Proving Correct Execution of TFHE’s Bootstrapping using plonky2.

For more information and link to RSVP, see the event luma page at https://luma.com/FHE.org-081.

Abstract

In this work we demonstrate for the first time that a full FHE bootstrapping operation can be proven using a SNARK in practice. We do so by designing an arithmetic circuit for the bootstrapping operation and prove it using plonky2.

We are able to prove the circuit on an AWS Hpc7a instance in under 20 minutes. Proof size is about 200kB and verification takes less than 10ms. As the basis of our bootstrapping operation we use TFHE’s programmable bootstrapping and modify it in a few places to more efficiently represent it as an arithmetic circuit (while maintaining full functionality and security).

In order to achieve our results in a memory-efficient way, we take advantage of the structure of the computation and plonky2’s ability to efficiently prove its own verification circuit to implement a recursion-based IVC scheme.

About the speakers

Louis Tremblay Thibault is a cryptography researcher at Zama and a PhD student at ÉTS Montréal. His research focuses on privacy-preserving verifiable computation.

Platform Note

We’ve recently switched from using Zoom for our meetups to Google Meet. The meetup link will remain the same (https://fhe.org/meetups/join). If you have any issues getting into the new meetup, please email us at contact@fhe.org.

Never miss an update

Join the discord server to discuss FHE related topics with the community: discord.fhe.org.

See you soon!

The FHE.org team

🇹🇼 FHE.org Taipei 2026 Conference Deadline

The deadline for submissions for the FHE.org 2026 conference, to be held in Taipei on March 8th, 2026, is just around the corner!

If you would like to present, submit your 2-4 page PDF on your FHE project, use-case, or demo for the Call for Presentations before November 1st, 23:59 AoE. Work already presented at other conferences, and any interesting presentations, demos, or tutorials, are welcome! Read full instructions on our website here: https://fhe.org/2026/cfp

If you’d like to register, use https://luma.com/fhe-org-conference-2026-tickets.

For students, reach out to us at contact@fhe.org from your academic email address and let us know you’d like to attend to apply for waiving your registration fees.

For organizations interested in showing their support alongside the list of annual sponsors for the conference, reach out to contact@fhe.org. See last year’s sponsors page for a list of previous sponsors.

🎤 Academic Conferences

In September, CHES was held in Kuala Lumpur, Malaysia, and there were a lot of papers presented on FHE topics:

• Designing a General-Purpose 8-bit (T)FHE Processor Abstraction by: Daphné Trama, Aymen Boudguiga, Pierre-Emmanuel Clet, Renaud Sirdey, and Nicolas Ye

• Sharing the Mask: TFHE Bootstrapping on Packed Messages by: Loris Bergerat, Charlotte Bonte, Benjamin R. Curtis, Jean-Baptiste Orfila, Pascal Paillier, and Samuel Tap

• Secure and efficient transciphering for FHE-based MPC by: Diego F. Aranha, Antonio Guimarães, Clément Hoffmann, and Pierrick Méaux

• SoK: FHE-Friendly Symmetric Ciphers and Transciphering by: Chao Niu, Benqiang Wei, Zhicong Huang, Zhaomin Yang, Cheng Hong, Meiqin Wang, and Tao Wei

• XBOOT: Free-XOR Gates for CKKS with Applications to Transciphering by:

  Chao Niu, Zhicong Huang, Zhaomin Yang, Yi Chen, Liang Kong, Cheng Hong, and Tao Wei

• TFHE Gets Real: an Efficient and Flexible Homomorphic Floating-Point Arithmetic by: Loris Bergerat, Ilaria Chillotti, Damien Ligier, Jean-Baptiste Orfila, and Samuel Tap

• Efficient Homomorphic Integer Computer from CKKS by Jaehyung Kim

• A New Perspective on Key Switching for BGV-like Schemes by Johannes Mono Tim Güneysu

• A Fast Heuristic for Mapping Boolean Circuits to Functional Bootstrapping by Sergiu Carpov

• VeloFHE: GPU Acceleration for FHEW and TFHE Bootstrapping by Shiyu Shen, Hao Yang, Zhe Liu, Ying Liu, Xianhui Lu, Wangchen Dai, Lu Zhou, Yunlei Zhao, and Ray C. C. Cheung

• Efficient and Compact Full-Domain Functional Bootstrapping via Subring Folding by Han Xia and Mingsheng Wang

• FINAL bootstrap acceleration on FPGA using DSP-free constant-multiplier NTTs by Jonas Bertels, Hilder V. L. Pereira, and Ingrid Verbauwhede

• REED: Chiplet-based Accelerator for Fully Homomorphic Encryption by Aikata Aikata, Ahmet Can Mert, Sunmin Kwon, Maxim Deryabin, and Sujoy Sinha Roy

• GPU Acceleration for FHEW/TFHE Bootstrapping by Yu Xiao, Feng-Hao Liu, Yu-Te Ku, Ming-Chien Ho, Chih-Fan Hsu, Ming-Ching Chang, Shih-Hao Hung, and Wei-Chao Chen

• Accelerating NTT with RISC-V Vector Extension for Fully Homomorphic Encryption by Tiago B. Rodrigues, Alexandre Rodrigues, Manuel Goulão, Pedro Tomás, and Leonel Sousa

Watch out for some of these papers, which will be presented at FHE.org meetups in the coming months!

🎤 Upcoming Meetups

Don’t miss the next meetup coming next Thursday, Accelerating NTT with RISC-V Vector Extension for Fully Homomorphic Encryption w/ Alexandre Rodrigues.

Other upcoming meetups by various presenters include:

• Proving Correct Execution of TFHE’s Bootstrapping using plonky2

• And more!

Couldn’t make it to a previous meetup? Check the meetups page on FHE.org for recordings and resources from all previous meetups.

Make sure you’re subscribed to this digest to get notifications of all future FHE.org Meetups as they are scheduled.

Got a paper or presentation you think the community might be interested in or would make a good meetup? Get in touch at contact@fhe.org.

📰🕺 Latest Updates from the FHE.org Community

• Previous Meetups and Meet the Community interviews you may have missed:

  • InsPIRe: Communication-Efficient PIR with Silent Preprocessing w/ Rasoul Akhavan Mahdavi

• Encrypted Matrix Multiplication Using 3-D Rotations w/ Shane Kosieradzki and Hannah Mahon

• Meet the Community w/ Rasoul Akhavan Mahdavi

• FHE.org Community:

  • Do you have an idea, something to share, a resource to add, or something you’d like to change about FHE.org? You can post any suggestions and proposals in the #meta channel on the FHE.org discord!

  • Interested in joining a reading group? Join the paper reading group in #reading-group. Introduce yourself there to get started!

• Don’t forget that the FHE.org website is open source and that anyone can add resources by simply opening a PR on Github: https://github.com/FHE-org/fhe-org.github.io.

💙 FHE.org is an open-source community of researchers and developers interested in Fully Homomorphic Encryption (FHE), if you’d like to contribute, join the community:

• On Discord

• On X

• On Linkedin

• On Mastodon

• On Bluesky

• On Farcaster

• On the official website

👉 You think something is missing from this FHE.org digest? Help us craft the next one, join the discussion on Discord.

This meetup features Alexandre Rodrigues, PhD student at INESC-ID, IST University of Lisbon, presenting Accelerating NTT with RISC-V Vector Extension for Fully Homomorphic Encryption.

For more information and link to RSVP, see the event luma page at https://luma.com/FHE.org-080.

Abstract

We target the optimization of FHE by leveraging vectorized implementations in RISC-V processors, using the RISC-V Vector (RVV) Extension. In particular, we accelerate the Number Theoretic Transform (NTT) and the Inverse-NTT (INTT), integrating our implementations in OpenFHE.

The specific contributions of our paper are:

1) A systematic analysis of the performance and memory access patterns of four widely used NTT/INTT algorithms, namely Cooley-Tukey/Gentelman-Sande and Korn-Lambiotte/Pease;

2) RVV-optimized implementations of these algorithms, including modular arithmetic routines and tailored butterfly structures and root-of-unity accesses;

3) The integration of our vectorized implementations into the OpenFHE library;

4) A comprehensive performance evaluation using two distinct computational platforms - a Vector Processing Unit (VPU) running on an FPGA and an out-of-order core simulated in gem5.

Our results show that the Korn-Lambiotte/Pease implementations outperform Cooley-Tukey/Gentelman-Sande, which are commonly used by state-of-the-art libraries (e.g. Intel HEXL). Our approach achieves significant speedups in both NTT benchmarks and complete FHE applications.

About the speakers

Alexandre Rodrigues is currently pursuing a PhD in Computing from Instituto Superior Técnico’s doctoral programme in Electrical and Computer Engineering.

His research interests include performance modelling, microarchitectural design and RISC-V.

Platform Note

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This meetup features Shane Kosieradzki, a Cryptographic Engineer at Crypto Asset Technology Labs, and Hannah Mahon, a Research Scientist at the Georgia Tech Research Institute, presenting Encrypted Matrix Multiplication Using 3-Dimensional Rotations.

For more information and link to RSVP, see the event luma page at https://luma.com/FHE.org-079.

Abstract

Fully homomorphic encryption (FHE) enables computations over encrypted data without the need for decryption. Recently there has been an increased interest in developing FHE based algorithms to facilitate encrypted matrix multiplication (EMM) due to rising data security concerns surrounding cyber-physical systems, sensor processing, blockchain, and machine learning.

​Presently, FHE operations have a high computational overhead, resulting in an increased need for low operational complexity algorithms to compensate. We present a novel matrix encoding and EMM algorithm for power-of-2 cyclotomic based rings, utilizing three-dimensional rotations which offer improvements over the one-dimensional rotations used in previous work. We encode each $d \times d$ matrix as a single, batch-encoded, ciphertext, with minimum ciphertext size $d^3$.

​The proposed algorithm improves the number of plaintext-ciphertext multiplications from $O(d)$ to $O(1)$ and the number of rotations from $O(d)$ to $O(\log_2 (d)$. In addition, our work supports rectangular matrix multiplication and matrix packing without incurring additional operations per execution. Benchmarks were obtained with a Microsoft SEAL implementation and compared against leading EMM algorithm, with our work performing $4$ times faster for $16 \times 16$ matrices on consumer hardware. Our algorithm is compatible with existing encrypted machine learning frameworks and can be a drop-in replacement for existing matrix multiplication algorithms for increased speed. The favorable time complexity is well suited for time sensitive encrypted algorithms such as computer vision, controls, and patient health monitoring.

About the speakers

Shane Kosieradzki is a Cryptographic Engineer at Crypto Asset Technology Labs, specializing in the development of Fully Homomorphic Encryption technology. In his current role he is working to develop next generation crypto-currency tools to empower law enforcement and government agencies to tackle the rising threat posed by digital assets.

​Hannah Mahon is a Research Scientist at the Georgia Tech Research Institute. Her research interests include algebraic geometry, fully homomorphic encryption, and formal verification of software and hardware.

Platform Note

We’ve recently switched from using Zoom for our meetups to Google Meet. The meetup link will remain the same (https://fhe.org/meetups/join). If you have any issues getting into the new meetup, please email us at contact@fhe.org.

Never miss an update

Join the discord server to discuss FHE related topics with the community: discord.fhe.org.

See you soon!

The FHE.org team