How to stay safe from repo-jacking
Repo-jacking is a specific type of supply chain attack. This blog post explains what it is, what the risk is, and what you can do to stay safe.
Kevin Backhouse
I’m a security researcher on the GitHub Security Lab team. I try to help make open source software more secure by searching for vulnerabilities and working with maintainers to get them fixed.
Posts by this author
Cueing up a calculator: an introduction to exploit development on Linux
Using CVE-2023-43641 as an example, I’ll explain how to develop an exploit for a memory corruption vulnerability on Linux. The exploit has to bypass several mitigations to achieve code execution.
Coordinated Disclosure: 1-Click RCE on GNOME (CVE-2023-43641)
CVE-2023-43641 is a vulnerability in libcue, which can lead to code execution by downloading a file on GNOME.
Four tips to keep your GitHub Actions workflows secure
Researchers from Purdue and NCSU have found a large number of command injection vulnerabilities in the workflows of projects on GitHub. Follow these four tips to keep your GitHub Actions workflows secure.
How to fix a ReDoS
Code scanning detects ReDoS vulnerabilities automatically, but fixing them isn’t always easy. This blog post describes a 4-step strategy for fixing ReDoS bugs.
Getting root on Ubuntu through wishful thinking
How to exploit a double-free vulnerability in Ubuntu’s accountsservice (CVE-2021-3939)
Blue-teaming for Exiv2: how to squash bugs by enrolling in OSS-Fuzz
OSS-Fuzz is Google’s awesome fuzzing service for open source projects. GitHub Security Lab’s @kevinbackhouse describes enrolling a project.
Blue-teaming for Exiv2: adding custom CodeQL queries to code scanning
The Exiv2 team tightened our security by enabling GitHub’s code scanning feature and adding custom queries tailored to the Exiv2 code base.
Blue-teaming for Exiv2: three rules of bug fixing for better OSS security
When you’re fixing a bug, especially a security vulnerability, you should add a regression test, fix the bug, and find & fix variants.
Blue-teaming for Exiv2: creating a security advisory process
This blog post is the first in a series about hardening the security of the Exiv2 project. My goal is to share tips that will help you harden the security of your own project.
Privilege escalation with polkit: How to get root on Linux with a seven-year-old bug
polkit is a system service installed by default on many Linux distributions. It’s used by systemd, so any Linux distribution that uses systemd also uses polkit.
How to get root on Ubuntu 20.04 by pretending nobody’s /home
Ubuntu 20.04 local privilege escalation using vulnerabilities in gdm3 and accountsservice (CVE-2020-16125, CVE-2020-16126, CVE-2020-16127)
Ubuntu whoopsie integer overflow vulnerability (CVE-2019-11484)
This is the fourth and final post in a series about Ubuntu’s crash reporting system. We’ll review CVE-2019-11484, a vulnerability in whoopsie which enables a local attacker to get a shell as the whoopsie user, thereby gaining the ability to read any crash report.
Ubuntu apport PID recycling security vulnerability (CVE-2019-15790)
This is the third post in a series about Ubuntu’s crash reporting system. We’ll review CVE-2019-15790, a vulnerability in apport that enables a local attacker to obtain the ASLR offsets for any process they can start (or restart).
Ubuntu apport TOCTOU security vulnerability (CVE-2019-7307)
This is the second post in our series about Ubuntu’s crash reporting system. We’ll review CVE-2019-7307, a TOCTOU vulnerability that enables a local attacker to include the contents of any file on the system in a crash report.
Whoopsie-daisy: Chaining accidental features of Ubuntu’s crash reporter to get Local Privilege Escalation
This post summarizes several security vulnerabilities in Ubuntu’s crash reporting system: CVE-2019-7307, CVE-2019-11476, CVE-2019-11481, CVE-2019-11484, CVE-2019-15790. When chained together, they allow an unprivileged user to read arbitrary files on the system.