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containedcritical

Malware in base65-11x

The npm package base65-11x was found to contain malware, potentially giving full control of affected systems to an outside entity. All systems with this package installed should be considered fully compromised.

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Disclosed
Last updated
Blast radius
Any system with the package installed or running
Ecosystems
Attack vectors
Affected entities
  • base65-11x

The npm package base65-11x was identified as containing malware. According to the GitHub advisory, any computer with this package installed or running should be considered fully compromised.\n\nThe advisory recommends that all secrets and keys stored on affected computers be rotated immediately from a different, uncompromised system. While the package should be removed, there is no guarantee that removal will eliminate all malicious software that may have been installed as a result of the package installation, given the potential for full system compromise.\n\nAffected users should treat their systems as potentially fully compromised and take appropriate incident response measures.

Indicators of compromise

Packages
  • base65-11x

Remediation

  • Immediately remove the base65-11x package from all systems
  • Rotate all secrets, keys, and credentials from a different, uncompromised computer
  • Assume full system compromise and conduct thorough forensic analysis
  • Monitor affected systems for signs of unauthorized access or persistence mechanisms
  • Consider rebuilding affected systems from clean media if full compromise is suspected

Sources

  1. GitHub Advisory GHSA-39c6-h85q-hpcw · GitHub Advisory Database

Cite this entry

"Malware in base65-11x." supplychainattack.org, Supply Chain Attack Incident Catalog. Disclosed August 11, 2026; last updated August 11, 2026. https://supplychainattack.org/incident/malware-in-base65-11x-1fa9ck

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