Hackers Injecting Malicious Code into GitHub Actions to Steal PyPI Tokens CyberDudeBivash — Threat Brief & Defensive Playbook
SUMMARY Attackers are modifying GitHub Actions workflows (via compromised accounts, malicious PRs, or forged commits) to add steps that exfiltrate PyPI (or other package registry) publishing tokens. With those tokens they publish backdoored packages or download private packages — a supply-chain multiplier. Defend by eliminating long-lived secrets, switching to OIDC/ephemeral credentials, hardening workflow controls, monitoring workflow changes and secret usage, and rotating tokens immediately if you suspect compromise. How attackers typically operate Gain write access to repo or CI/CD config (via compromised developer account, stolen token, privilege abuse, or merge of malicious PR). Modify or add a workflow file that runs in the repo’s runner context (self-hosted or GitHub-hosted). Add steps that read repository secrets (e.g., PYPI_TOKEN ) or create credentials files ( ~/.pypirc ), then send the token to attacker-controlled endpoints or push a malicious p...