SleeperGem Uses Three Malicious RubyGems Packages to Target Developer Machines
Jul 20, 2026
Malware / Application Security
Cybersecurity researchers have flagged a new software supply chain attack codenamed SleeperGem targeting the Ruby ecosystem after three malicious gems were published to RubyGems with the end goal of serving additional payloads. The rogue gems are listed below - git_credential_manager (versions 2.8.0, 2.8.1, 2.8.2, 2.8.3) - Published on July 18, 2026 Dendreo (versions 1.1.3, 1.1.4) - Published on October 14, 2017 fastlane-plugin-run_tests_firebase_testlab (version 0.3.2) - Published on February 06, 2018 "Each malicious release is a loader," StepSecurity said in an analysis. "It fetches a second stage from an attacker controlled Forgejo host, checks whether it is running in a build system and skips if it is, and on a developer machine it drops a native daemon and installs persistence." One aspect of the attack that immediately stands out is that "git_credential_manager" impersonates the official Microsoft Git Credential Manager, while t...