During an assumed breach ops via a virtual desktop interface, we discovered a wildcard allow firewall rule for the Azure Blob Storage service. We proved that even with restrictions in place, it was still possible to reach the Internet. Afterwards, we thought of abusing this firewall misconfiguration (recommended by Microsoft) in a much more useful way. To demonstrate that I built a SOCKS5 proxy that uses blobs to tunnel traffic to the target's internal network.

The following article explains how, during an audit, we examined Moodle (v4.4.3) and found ways of bypassing all the restrictions preventing SSRF vulnerabilities from being exploited.

The Open Source Technology Improvement Fund, Inc, thanks to funding provided by Sovereign Tech Fund, engaged with Quarkslab to perform a security audit of PHP-SRC, the interpreter of the PHP language.

A signature verification bypass in a function that verifies the integrity of ZIP archives in the AOSP framework

A technical exploration of a trivial Local Privilege Escalation Vulnerability in CCleaner <= v1.18.30 on macOS.

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.

A technical exploration of modern phishing tactics, from basic HTML pages to advanced MFA-bypassing techniques, with analysis of infrastructure setup and delivery methods used by phishers in 2025.

Allbridge mandated Quarkslab to perform an audit of their updated version of Estrela, an automated market maker for Stellar built on Soroban.

The following article describes how, during an "assumed breach" security audit, we compromised multiple web applications on our client's network in order to carry out a watering hole attack by installing fake Single Sign-On pages on the compromised servers. This article is the first of a two-part series and explains why it is not enough to just check for CVEs, and why we should dive deep into the code to look for new vulnerabilities in old code bases. We will take phpMyAdmin version 2.11.5 as an example, as this is the version we encountered during the audit.

In this series of articles we describe how, during an "assumed breach" security audit, we compromised multiple web applications on our client's network to carry out a watering hole attack by installing fake Single Sign-On pages on compromised servers. In our second episode we take a look at SOPlanning, a project management application that we encountered during the audit.