Cybersecurity researchers have warned of malicious images pushed to the official "checkmarx/kics" Docker Hub repository. In an alert published today, software supply chain security company Socket revealed that unknown threat actors managed to have overwritten existing tags, including v2.1.20 and alpine, while also introducing a new v2.1.21 tag that does not correspond to an official release. The Docker repository has been archived as of writing. "Analysis of the poisoned image indicates that the bundled KICS binary was modified to include data collection and exfiltration capabilities not present in the legitimate version," Socket said. "The malware could generate an uncensored scan report, encrypt it, and send it to an external endpoint, creating a serious risk for teams using KICS to scan infrastructure-as-code files that may contain credentials or other sensitive configuration data." Further analysis of the incident has uncovered that related Checkmarx developer tooling may also have been affected, such as recent Microsoft Visual Studio Code extension releases that come with malicious code to download and run a remote addon through the Bun runtime. "The behavior appeared in versions 1.17.0 and 1.19.0, was removed in 1.18.0, and relied on a hard-coded GitHub URL to fetch and run additional JavaScript without user confirmation or integrity verification," Socket added. The list of affected extensions is below - - checkmarx/cx-dev-assist@1.17.0 - checkmarx/cx-dev-assist@1.19.0 - checkmarx/ast-results@2.63.0 - checkmarx/ast-results@2.66.0 Specifically, the compromised Checkmarx extensions come with a multi-stage credential theft and propagation component that, upon extension activation, is downloaded from a GitHub URL as "mcpAddon.js." The file name implies an attempt to masquerade the malware as a hidden Model Context Protocol (MCP) feature. "The attacker began by injecting a backdated commit (68ed490b) into the 'Checkmarx/ast-vscode-extension' repository," Socket said. "This commit was deliberately crafted to appear legitimate: it was spoofed to look like it was authored in 2022,