Supply Chain Risk: Exploiting Abandoned Domains of Linux Package Maintainers

Background: In my recent articles, we discussed a lot various supply chain attack scenarios. This led me to think about a new type of supply chain attack, specifically targeting Linux package maintainers. It’s no secret that the Linux community is one of the most vibrant and driven groups, powering much of our digital infrastructure. However, because many packages are maintained for a long time, some developers eventually leave the industry, and their maintained packages—along with the source code—can be left unattended.

Attack scenario: Linux developers often use their own domains, which may have been acquired years ago. If these domains are abandoned, attackers can potentially register the expired domains. Once they control the domain, attackers may be able to recover accounts associated with it and push malicious code to version control repositories. This harmful code could then be mistakenly used by regular users or even by Linux systems themselves. The real challenge, however, is identifying which maintainer domains have been abandoned.

Defense mechanisms implementation: I have been thinking about this challenge for a long time and have come up with a solution. What if we monitor the GPG-assigned emails of package maintainers in our local environment? We can extract the domain from each email and perform a simple dig request to check if the extracted domain is still resolving. As result we can retrieve this information and send to our SIEM systems for further risk measuring

Conclsuion: I predict that the risk of supply chain attacks will increase, and that the root cause may not always be phishing or sophisticated attack methods. Instead, attackers could exploit simple attack vectors. For this reason, you should begin considering this direction to reduce risks in your infrastructure and start implementing action items.