Checkmarx’s software engineers are still working to remove a malicious version of the code security outfit's Jenkins plugin after detecting an unauthorized upload over the weekend. It updated customers on Saturday, May 9, after discovering a version of its AST Scanner, which is used for security scans in Jenkins CI pipelines, was made available via the Jenkins Marketplace. “We are aware that a modified version of the Checkmarx Jenkins AST plugin was published to the Jenkins Marketplace,” it said in a statement. “We are in the process of publishing a new version of this plug-in.” Versions published as of May 9, 2026, should not be trusted, it added, before urging all users to check they’re running the correct release (2.0.13-829.vc72453fa_1c16) published on December 17, 2025. Installed by several hundred controllers, the plugin remains available at the time of writing, and appears as the most recently available version, although pull requests actioned on Monday morning suggest this will soon be pulled down. “What makes this particularly dangerous for Jenkins users is the trust model at play,” said SOCRadar in its coverage. “The Checkmarx Jenkins plugin is a tool people install specifically to improve the security of their pipelines. “A backdoored version doesn’t just compromise one project; it rides trusted infrastructure into every build pipeline it touches, with access to source code, environment variables, tokens, and whatever secrets the runner can see.” Security engineer Adnan Khan spotted the compromise quickly over the weekend. The crew behind the early supply chain attack affecting Checkmarx in April, TeamPCP, defaced the company’s GitHub and published six packages, each with a description alluding to the Shai-Hulud wormable malware. These packages no longer appear on Checkmarx’s GitHub, but TeamPCP made multiple changes to the AST plugins page, renaming it to “Checkmarx-Fully-Hacked-by-TeamPCP-and-Their-Customers-Should-Cancel-Now,” and altering the description to claim CheckMarx failed to rotate its secrets. The latest infiltration of Checkmarx’s internals marks the third time TeamPCP has compromised the company’s packages in as many months. As previously seen in The Register, the crooks successfully targeted Checkmarx’s AST plugin for GitHub Actions and its KICS static analysis tool back in March, deploying credential-stealing malware. SOCRadar said the latest TeamPCP compromise of the Jenkins plugin suggests that either TeamPCP was telling the truth about Checkmarx’s secrets rotation, or its members took advantage of an additional persistence mechanism that the security vendor failed to notice during its response to the March intrusion. ®
The Challenge As stated in PART 1 of this blog, the Windows endpoint defense technology stack in a mature organization represents a challenge for Red Teamer initial access operations. For […]
Login
