r/crypto

FHE.org 2025 conference video and poster resources including talks from Craig Gentry and other well known FHE cryptographers

SAS-ROS Cipher and its Encryption Algorithms (SAS-RCS & SAS-RBS) – Seeking Cryptographic Review

I'm an independent developer with a long-standing interest in cryptographic systems and secure algorithm design. Over the past year, I’ve been working on a symmetric key-based random substitution cipher and a pair of encryption algorithms built on it. This effort …

Physically Uncloneable Functions (PUFs)

Recently come to learn about [PUFs](https://en.wikipedia.org/wiki/Physical_unclonable_function). Does anyone know of any consumer products using them and what they're being used for?

For E2EE apps like Signal what stops the server from giving you a fake public key for a user?

Say I want to send a message to Alice. To encrypt my message to Alice doesn't Signal have to send me her public key? What stops them from sending me a fake public key? I believe that at some point …

Clubcards for the WebPKI: smaller certificate revocation tests in theory and practice

To implement public key infrastructure for protocols such as TLS, parties need to check not only that certificates are properly signed, but also that they haven't been revoked, due to e.g. key compromise. Revocation was originally implemented using certificate revocation …

Apple is now legally allowed to talk about the UK's backdoor demands

Join us in two weeks on Apr 17th at 3PM CEST for an FHE.org meetup with Mohammed Lemou, Senior Researcher (Directeur de Recherche) at the French National Center for Scientific Research (CNRS), presenting "Exploring General Cyclotomic Rings in Torus-Based Fully Homomorphic Encryption: Part I"

Forming a Cryptography and Number Theory reading group

Hi everyone! I want to start a virtual reading group focused on cryptography and number theory, where we can learn together in a collaborative environment. Whether you’re a beginner or have some background, all you need is curiosity! Currently I …

Adaptively-Secure Big-Key Identity-Based Encryption

JS + WebRTC + WebCrypto = P2P E2EE Messaging PWA

Selhosted P2P E2EE File Transfer & Messaging PWA * The app: [chat.positive-intentions.com](http://chat.positive-intentions.com/) * The source: [https://github.com/positive-intentions/chat](https://github.com/positive-intentions/chat) * More information about the app: [https://positive-intentions.com/docs/apps/chat](https://positive-intentions.com/docs/apps/chat) * Follow the subreddit to keep updated about the app: [r/positive\_intentions](https://www.reddit.com/r/positive_intentions/)