Gentoo Linux reported on June 28 that its GitHub repository was breached, with attackers planting malicious code in the open-source Linux project's account.
The malware that was found on the Gentoo Linux GitHub project site was designed to specifically remove all of the files on a victim's system.
"Today 28 June at approximately 20:20 UTC unknown individuals have gained control of the Github Gentoo organization, and modified the content of repositories as well as pages there," Gentoo warned in an advisory. "We are still working to determine the exact extent and to regain control of the organization and its repositories. All Gentoo code hosted on github should for the moment be considered compromised."
Gentoo Linux is a popular open-source, community-based Linux distribution that works on a rolling release model that is continuously updated.
In a mailing list message, Gentoo developer Francisco Blas Izquierdo Riera wrote that the attackers "… replaced the portage and musl-dev trees with malicious versions of the ebuilds intended to try removing all of your files." Portage is Gentoo's package management system and is the way that software is distributed to Gentoo users.
In response to the attack, Gentoo developers have locked down the GitHub project to prevent further damage. The root cause of the attack appears to be a compromised account that has now been locked out. Gentoo is now going through the process of re-adding developers to its GitHub account and is requiring that all developers add two-factor authentication (2FA) to their GitHub accounts to be re-admitted.
The potential impact of the attack, however, is somewhat limited for the core development of the project, since development occurs on Gentoo Foundation-operated hardware and not on GitHub. The GitHub site was a mirror from which users may have downloaded, exposing an unknown number of users to risk.
Gentoo is not the first Linux distribution to be the victim of an attack that aims to compromise developer code.
Back in August 2008, attackers breached the servers of Red Hat's Fedora community Linux distribution. In September 2011, the main Linux kernel development site, kernel.org, was breached via a compromised user credential. In the Linux kernel incident, development continued on GitHub, while the main kernel.org site was down. Attackers also took aim at Linux Mint in February 2016, planting a backdoor in the distribution forum that was quickly remediated.
Sean Michael Kerner is a senior editor at eWEEK and InternetNews.com. Follow him on Twitter @TechJournalist.