A malicious version of the Checkmarx Jenkins Application Security Testing (AST) plugin was uploaded to the Jenkins Marketplace over the weekend in a latest supply-chain attack linked to the TeamPCP hacker group.
Checkmarx confirmed that a modified version of its Jenkins AST plugin had been published outside the company’s official release pipeline. The plugin integrates security scanning into Jenkins, one of the world’s most widely used CI/CD automation platforms for software development and deployment.
“We are aware that a modified version of the Checkmarx Jenkins AST plugin was published to the Jenkins Marketplace,” the company said in a security update. “We are in the process of publishing a new version of this plug-in.”
Security researchers say TeamPCP gained access to Checkmarx GitHub repositories using credentials stolen during the March compromise of the Trivy vulnerability scanner project. According to offensive security engineer Adnand Khan, the attackers backdoored the Jenkins plugin to deploy credential-stealing malware.
The rogue plugin version, identified as 2026.5.09, was uploaded to repo.jenkins-ci.org on May 9. Researchers noted several red flags, including the absence of a GitHub release or git tag and a versioning format that differed from the company’s standard release scheme.
The incident follows earlier breaches involving Checkmarx tools, including malicious versions of the company’s KICS analysis utility distributed through Docker, Open VSX, and VSCode marketplaces. The compromised releases reportedly harvested sensitive data from developer environments.
Customers are recommended to verify they are using plugin version 2.0.13-829.vc72453fa_1c16, released on December 17, 2025, or an earlier trusted release. Users who downloaded the malicious version are advised to rotate credentials as soon as possible and check systems for signs of persistence or lateral movement.
Checkmarx said that its GitHub repositories are isolated from customer production systems and do not contain customer data.The company has also published indicators of compromise (IoCs) to help defenders identify malicious artifacts in their environments.