Research and Development


In this post we look at at one of many security problems that pentesters and security auditors find in setUID programs. It’s fairly common for child processes to inherit any open file handles in the parent process (though there are ways to avoid this). In certain cases this can present a security flaw. This is what we’ll look at in the context of setUID programs on Linux. Continue reading

Modern autonomous vehicles use a number of sensors to analyse their surroundings and act upon changes in their environment. A brilliant idea in theory, but how much of this sensory information can we actually trust? Cisco’s Security Advisory R&D team, a.k.a. Portcullis Labs, decided to investigate further. Continue reading

In the modern age, where computers are used for nearly everything we do, the damage that can be caused to a company by cyber-attacks is substantial, with companies losing millions in regulatory fines, compensation and declining share prices. While some of these breaches have been caused by vulnerabilities within the target company’s infrastructure/software, a large quantity of them began with a phishing attack. Continue reading

It’s not every day we get to assess biometric systems from a security perspective, they are still somewhat esoteric and testing them doesn’t quite fit with the usual slew of things that come along with being a security consultant. Recent engagements reminded us of just how interesting this facet of the industry can be and so we decided to write up a little something around biometrics. This article will cover some of the history and the basics of biometrics and some of the biometric-centric attacks you may come across… Continue reading

This year, one member of the Portcullis team went to one of the biggest security events in France: SSTIC (Symposium sur la sécurité des technologies de l’information et des communications). This post will highlight the most interesting presentations. Many of the slides, articles and videos are available on the SSTIC web site, but they are mostly in French. Continue reading

It is a topic that often comes up on client engagements, usually when running structured build reviews of Linux “gold builds”, but occasionally when trying to explain in detail how we used a Linux system to pivot internally.

SetUID and setGID files are inevitably a risk, potentially allowing attackers to elevate privileges to root from a basic user. When shared out on SMB or NFS shares they can spread the risk even further. Continue reading

Here at Portcullis, we are frequently involved in “red team” exercises, which means we subject an organisation’s information security systems to rigorous testing and analysis. The opposite of a red team is a “blue team”. A blue team attempts to identify and stop the red team from compromising systems. One of the techniques used when red teaming is to write malicious code to test the security systems of our clients. One of the issues we face resides in the fact that we need to bypass sandbox systems that analyse our files in real-time to identify if the potentially malicious file should be blocked and Indicators Of Compromise (IOCs) generated or if the files are benign and safe. At the same time, blue teams that catch our files will try to reverse engineer them in order to understand how we may be compromising systems. Even though the last point is not really relevant for us (ultimately we’re not the bad guys), the first point is. Continue reading