Researchers Spot Supply Chain Attack Targeting GitLab CI Pipelines

Security researchers at SentinelLabs are calling attention to a software chain supply attack targeting Rust developers with malware aimed directly at infecting GitLab Continuous Integration (CI) pipelines.

The campaign, dubbed CrateDepression, combines typosquatting and the impersonation of a known Rust developer to push a malicious ‘crate’ hosted on the Rust dependency community repository.  (Editor’s note: A crate is a compilation unit in Rust). 

The malicious crate was swiftly flagged and removed but SentinelLabs researchers found a second-stage payload exclusively built to  Gitlab CI pipelines, signaling a risk of further larger-scale supply-chain attacks.

“Given the nature of the victims targeted, this attack would serve as an enabler for subsequent supply-chain attacks at a larger-scale relative to the development pipelines infected,” SentinelLabs said in a technical report documenting its findings.

“An infected machine is inspected for the GITLAB_CI environment variable in an attempt to identify Continuous Integration (CI) pipelines for software development. On those systems, the attacker(s) pull a next-stage payload built on the ‘red-teaming’ post-exploitation framework Mythic,” SentinelLabs explained.

This second-stage payload contains a switch with a large array of tasking options, including the ability to capture screenshots, keyboard strokes, and the uploading and downloading of files. On macOS, the operator can choose to persist by either or both of a LaunchAgent/Daemon and a LoginItem. 

SentinelLabs said an investigation by the crates.io security team and Rust Security Response working group turned up 15 iterative versions of the malicious ‘rustdecimal’ as the attacker(s) tested different approaches and refinements.   

“While the ultimate intent of the attacker(s) is unknown, the intended targeting could lead to subsequent larger scale supply-chain attacks depending on the GitLab CI pipelines infected.” 

“Software supply-chain attacks have gone from a rare occurrence to a highly desirable approach for attackers to ‘fish with dynamite’ in an attempt to infect entire user populations at once,” SentinelLabs added.

Related: Codecov Bash Uploader Dev Tool Compromised in Supply Chain Compromise

Related: Critical GoCD Authentication Flaw Exposes Software Supply Chain

Related: Google Intros SLSA Framework to Enforce Supply Chain Integrity