Gérald Doussot

Technical Advisory – Ollama DNS Rebinding Attack (CVE-2024-28224)

Ollama is an open-source system for running and managing large language models (LLMs). NCC Group identified a DNS rebinding vulnerability in Ollama that permits attackers to access its API without authorization, and perform various malicious activities, such as exfiltrating sensitive file data from vulnerable systems.

Read more

Public Report – Solana Program Library ZK-Token Security Assessment

In August 2022, Solana Foundation engaged NCC Group to conduct a security assessment of the ZK-Token SDK, a collection of open-source functions and types that implement the core cryptographic functionalities of the Solana Program Library (SPL) Confidential Token extension. These functionalities are homomorphic encryption and associated proofs used to demonstrate…

Read more

Constant-Time Data Processing At a Secret Offset, Privacy and QUIC

Introduction NCC Group Cryptography Services team assessed security aspects of several implementations of the QUIC protocol. During the course of their reviews, the team found a number of recurrent cryptography side channel findings of arguably negligible privacy risk to users, across these implementations. However, repetition in itself makes these findings…

Read more

Software Verification and Analysis Using Z3

We provide a technical introduction on how to leverage the Z3 Theorem Prover to reason about the correctness of cryptographic software, protocols and otherwise, and to identify potential security vulnerabilities. We cover two distinct use cases: modeling and analysis of an algorithm documented in an old version of the QUIC…

Read more

January 29, 2021

32 mins read

Read more

Technical Advisory – wolfSSL TLS 1.3 Client Man-in-the-Middle Attack (CVE-2020-24613)

wolfSSL is a C-language-based SSL/TLS library targeted at IoT, embedded, and RTOS environments. wolfSSL incorrectly implements the TLS 1.3 client state machine. This allows attackers in a privileged network position to completely impersonate any TLS 1.3 servers and read or modify potentially sensitive information between clients using the wolfSSL library…

Read more

Smart Contracts Inside SGX Enclaves: Common Security Bug Patterns

Running smart contracts in a Trusted Execution Environment (TEE) such as Intel Software Guard Extensions (SGX) to preserve the confidentiality of blockchain transactions is a novel and not widely understood technique. In this blog post, we point out several bug classes that we observed in confidential smart contract designs and…

Read more