How to perform snapshot-based coverage-guided fuzzing on Windows kernel components using Rewind, a tool we have just published on Github.

This article describes how Windows Defender implements its network inspection feature inside the kernel through the use of WFP (Windows Filtering Platform), how the device object’s security descriptor protects it from being exposed to potential vulnerabilities and details some bugs I found. As a complement to this post, a small utility is released to test the different bugs.

Tear-off techniques to the next level.

Oxen [1] mandated Quarkslab to perform an audit of their instant messaging solution Session [2]. This application, forked from Signal, aims to improve users privacy by using an onion routing mechanism [3]. This mechanism differs from Tor's one by requiring a deposit in their own cryptocurrency to operate a Service Node (Snode [4] ), the Oxen equivalent of a Tor Entry, Relay or Exit Node. While reviewing the architecture of this solution, we found some issues and provided recommendations to improve parts of the implementations.

This post is a quick vulnerability report summary for a vulnerability we found while fuzzing the TCP/IP stack CycloneTCP.

In this blog post we analyze a denial of service vulnerability affecting the IPv6 stack of Windows. This issue, whose root cause can be found in the mishandling of IPv6 fragments, was patched by Microsoft in their February 2021 security bulletin.

A quick introduction to Android Emuroot, a Python script that allows to get root privileges on the fly on an Android Virtual Device (AVD). It explains the reverse engineering steps needed for the script to work with recent AVDs and provides a preview of specific Linux kernel structures in memory.

This blog post introduces the release 0.8.0 of QBDI.

This blog post provides details about four vulnerabilities we found in the IPv6 stack of FreeBSD, more specifically in rtsold(8), the router solicitation daemon. The bugs affected all supported versions of FreeBSD, and the most severe of them could allow an attacker attached to the same physical link to gain remote code execution as root on vulnerable systems. The vulnerabilities were discovered and reported to FreeBSD Security Team in November 2020. FreeBSD issued fixes for these bugs on December 1st, 2020 along with security advisory FreeBSD-SA-20:32.rtsold.

The Ethereum Foundation mandated Quarkslab to perform an audit of the herumi libraries. They provide an API to perform BLS signatures, one of the core components of the new iteration of the Ethereum blockchain, named Ethereum 2.0. While reviewing the architecture of these libraries, their back ends and the adherence with the ongoing RFCs to standardize BLS signature usage, we found some issues primarily regarding their design. Although these are not considered critical, they impact the overall reliability of the libraries. We provide recommendations to improve the design of the libraries, the readability of the code and the usability of both projects.