This campaign involves a worm-like compromise of over 50 npm packages across multiple namespaces such as @tanstack, @mistralai, @uipath, @squawk, and safe-action. The malicious code activates during installation, downloading the Bun runtime to execute a payload that harvests GitHub credentials and cloud secrets. It specifically targets AWS environments by querying the Instance Metadata Service (IMDS) and attempts privilege escalation through AWS STS and SSM endpoints across multiple regions. The stolen credentials are then used automatically to publish additional malicious package versions under different maintainer accounts, enabling self-propagation. The attack employs a drop-and-execute method and uses a command-and-control domain (git-tanstack.com) designed to mimic legitimate tanstack.com traffic, consistent with previous Shai-Hulud-style compromises.

The attack results in theft of GitHub credentials and cloud secrets, enabling unauthorized access to AWS environments. This can lead to privilege escalation and further compromise of cloud resources. The self-propagating nature of the attack increases the risk of widespread supply chain contamination across npm packages. The use of stolen credentials to publish malicious package versions undermines trust in affected namespaces and can lead to further downstream infections.

No official patch or fix is indicated for the compromised packages. Organizations should immediately rotate all GitHub credentials and audit AWS credentials for unauthorized use. Monitoring for suspicious activity related to npm package publishing and AWS access is recommended. Due to the self-propagating nature of the attack, affected maintainers should review their package integrity and consider removing or rebuilding compromised packages. Follow vendor or repository advisories for updates and remediation guidance.