We look into the supply chain saga of the XZ Utils backdoor. It's a wild story of a carefully planned long con to add malicious code to a commonly used package that many SSH connections rely on. It hits themes from social engineering and abuse of trust to obscuring the changes and suppressing warnings. It also has a few lessons about software development, the social and economic dynamics of open source, and strategies for patching software. It's an exciting topic partially because so much other appsec is boring. And that boring stuff is important to get right first. We also talk about what parts of this that orgs should be worried about and what types of threats they should be prioritizing instead. Segment Resources: https://tukaani.org/xz-backdoor/ https://news.risky.biz/risky-biz-news-supply-chain-attack-in-linuxland/ https://www.zdnet.com/article/this-backdoor-almost-infected-linux-everywhere-the-xz-utils-close-call/#ftag=RSSbaffb68 https://therecord.media/malicious-backdoor-code-linux-red-hat-cisa https://www.cisa.gov/news-events/alerts/2024/03/29/reported-supply-chain-compromise-affecting-xz-utils-data-compression-library-cve-2024-3094 https://duo.com/decipher/carefully-crafted-campaign-led-to-xz-utils-backdoor https://boehs.org/node/everything-i-know-about-the-xz-backdoor Show Notes: https://securityweekly.com/asw-280