Tag: cryptography

In this blogpost, we first review the landscape of Post-Quantum Cryptography implementations across some of the most popular cryptographic libraries. Following that, we present the results of a differential fuzzing campaign on few of the presented implementations.

At the request of the Open Source Technology Improvement Fund (OSTIF), Quarkslab performed a security audit of mbedTLS, evaluating the security of the changes in version 4.0.

Passive Optical Networks (PONs) connect end-users to infrastructure using optical fibre in the last kilometre (Fibre-to-the-x). This article provides a technical overview of the security features in ITU-T specifications: Gigabit-capable PON (GPON), 10-Gigabit-capable PON (XG-PON), 10-Gigabit-capable Symmetric PON (XGS-PON), Next-generation PON 2 (NG-PON2), and 50-Gigabit-capable PON (50G-PON). The analysis covers authentication schemes, key derivation, encryption methods, and associated security implications.

The OSTIF collaborated with Quarkslab to conduct a security audit of Paramiko, a pure-Python implementation of SSHv2 that provides both client- and server-side functionality. Given the sensitivity and importance of the target, the review focused not only on Paramiko itself but also on its dependencies. The assessment covered its interaction with rust-openssl bindings, the use of secure entropy sources, adherence to constant-time requirements, as well as code quality, testing practices, and the CI/CD pipeline, with the goal of identifying opportunities for further hardening.

The internship season is back at Quarkslab! Our internship positions cover a wide range of topics and expertise, and aim at tackling new challenges in various fields.

Signal recently announced the introduction of another layer of post-quantum cryptography to their protocol, this time in their ratcheting mechanism. Let's take a look!

Following the introduction of crypto-condor and differential fuzzing in earlier blogposts, we showcase a use case where Quarsklab's automated test suite for cryptographic implementations allowed us to improve the reference implementation of the recently standardized HQC scheme.

Following a brief introduction to differential fuzzing, this blog post reviews the leading tools that leverage it for testing cryptographic primitives. In the second half, we present a method for creating a differential fuzzer along with the results we obtained.

In this blog post we present crypto-condor, an open-source test suite for compliance testing of implementations of cryptographic primitives.

We studied the most secure static encrypted nonce variant of "MIFARE Classic compatible" cards -- meant to resist all known card-only attacks -- and developed new attacks defeating it, uncovering a hardware backdoor in the process. And that's only the beginning...