Malware in refbase-mcp
Malware was discovered in the npm package refbase-mcp. Systems with this package installed or running should be considered fully compromised and require immediate remediation.
- Disclosed
- Last updated
- Blast radius
- Any system with the package installed or running
- Ecosystems
- Attack vectors
- Affected entities
- refbase-mcp
A malware incident was identified in the npm package refbase-mcp, published via GitHub Advisory GHSA-5xcj-w4qg-g78g on July 31, 2026.\n\nAny computer with this package installed or running is considered fully compromised. The malware may have granted outside entities full control of affected systems.\n\nImmediate remediation requires rotating all secrets and keys from a different, uncompromised computer. While the package should be removed, complete removal of all malicious software cannot be guaranteed due to the level of system compromise.\n\nUsers should assume that removing the package alone is insufficient to fully remediate the compromise.
Indicators of compromise
- Packages
- refbase-mcp
Remediation
- Immediately rotate all secrets, keys, and credentials from a different, uncompromised computer
- Remove the refbase-mcp package from all affected systems
- Perform a full security audit and malware scan of all systems that had the package installed
- Review system logs and access logs for signs of unauthorized activity during the period the package was installed
- Consider full system reimaging or replacement if the package was installed on critical systems
Sources
- GitHub Advisory GHSA-5xcj-w4qg-g78g · GitHub Advisory Database
Cite this entry
"Malware in refbase-mcp." supplychainattack.org, Supply Chain Attack Incident Catalog. Disclosed July 31, 2026; last updated July 31, 2026. https://supplychainattack.org/incident/malware-in-refbase-mcp-1mg3xm
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