Malware in leb128x
The npm package leb128x was found to contain malware that grants full system compromise to attackers. Any computer with this package installed or running should be considered fully compromised and all secrets and keys rotated immediately from a different machine.
- Disclosed
- Last updated
- Blast radius
- Any system with the package installed or running
- Ecosystems
- Attack vectors
- Affected entities
- leb128xnpm package containing malware
The npm package leb128x has been identified as containing malware. According to the GitHub Advisory (GHSA-p98p-7p39-8v79), any computer that has 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 computer. 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 initial compromise, given that the attacker may have gained full control of the system.\n\nUsers should treat any system that has run this package as potentially containing persistent malware and take appropriate incident response measures.
Indicators of compromise
- Packages
- leb128x
Remediation
- Immediately remove the leb128x package from all systems
- Rotate all secrets, API keys, and credentials from a different, uncompromised computer
- Assume full system compromise and perform forensic analysis or rebuild affected systems
- Review system logs and network traffic for signs of unauthorized access or data exfiltration
- Monitor for any suspicious activity on systems that had this package installed
Sources
- GitHub Advisory GHSA-p98p-7p39-8v79 · GitHub Advisory Database
Cite this entry
"Malware in leb128x." supplychainattack.org, Supply Chain Attack Incident Catalog. Disclosed August 17, 2026; last updated August 17, 2026. https://supplychainattack.org/incident/malware-in-leb128x-12e5wb
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