2025-09-15 –, Main Room
As a consumer of releases of open-source tools hosted on GitHub (you are one if you e.g. use terraform to deploy your cloud infrastructure), have you ever wondered if a release may include malicious code? And as a maintainer of such releases, have you ever wondered "How might I sneak some malicious code into my GitHub releases"?
I have done both, since as I am not only a maintainer of an (openly) malicious terraform provider, but also a red teamer with a focus on cloud and CI/CD, and thus stealth. So I sat down and explored how a malicious insider could manipulate their releases without ever touching the application code directly. I wanted to find ways to do that with only minimal changes to the build pipeline that is defined in a GitHub Action that do not obviously look suspicious.
Over time I identified three "classes" of attacks, all targeting my own build pipelines that were creating releases. During the talk I will walk you through all three of them and show five examples on how do execute them stealthily to create inconspicuous releases on GitHub. By showing the attacks I hope to spark some questions about the security of your own cloud infrastructure deployment pipelines that rely on third-party releases (like e.g. terraform providers). The good news for defenders: for (almost) all of the attack vectors I am able to point out ideas on detection and thus mitigation if you want to take a closer look at your own supply chain.
Hi! I am a red teamer, and I love it. I especially enjoy dealing with cloud, identity providers, and CI/CD pipelines. I have been using "the cloud" since 2015 as a data engineer and later team lead for a data team. In 2023 I switched sides and became a penetration tester and trainer for offensive and defensive cloud security. Now, I work in an internal red team focussing on cloud, CI/CD, and the related processes. Next to security stuff I love long runs and more security stuff.