GhostAction Campaign: How Compromised GitHub Maintainers Exposed Thousands of Repositories
The GhostAction campaign, active since September 2025, has escalated dramatically in October 2026 with attackers compromising high-profile GitHub maintainer accounts including Takashi Kitao (pyxel game engine) and Henry Wu (Uber's athenadriver author). Using stolen personal access tokens, threat actors injected malicious GitHub Actions workflows disguised as security audits into over 500 repositories across tens of thousands of projects. These workflows systematically exfiltrate CI/CD secrets, cloud credentials, AI API keys, and historical git data to attacker-controlled infrastructure via unencrypted HTTP connections, representing one of the largest supply chain attacks targeting developer infrastructure. This incident highlights the critical vulnerability of modern software supply chains as organizations increasingly rely on automated CI/CD pipelines and cloud-native development practices. The attack's sophisticated targeting of maintainer accounts and abuse of trusted automation workflows demonstrates how threat actors are evolving to exploit the interconnected nature of open-source ecosystems.
Kill Chain
