Malware in mjs-biginteger
Malware was discovered in the npm package mjs-biginteger. Systems with this package installed are considered fully compromised and require immediate remediation.
- Disclosed
- Last updated
- Blast radius
- Any system with the package installed
- Ecosystems
- Attack vectors
- Affected entities
- mjs-bigintegernpm package
The npm package mjs-biginteger was found to contain malware. According to the GitHub Advisory (GHSA-798w-xm3v-cfx3), 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, as the attacker may have gained full control of the system.\n\nThis represents a critical supply chain compromise affecting the npm ecosystem.
Indicators of compromise
- Packages
- mjs-biginteger
Remediation
- Immediately rotate all secrets, API keys, and credentials from a different, uncompromised computer
- Remove the mjs-biginteger package from all affected systems
- Conduct a full security audit of any system that had this package installed
- Review system logs for unauthorized access or activity during the period the package was installed
- Consider the affected system(s) potentially compromised and plan for full rebuild if critical infrastructure
Sources
- GitHub Advisory GHSA-798w-xm3v-cfx3 · GitHub Advisory Database
Cite this entry
"Malware in mjs-biginteger." supplychainattack.org, Supply Chain Attack Incident Catalog. Disclosed July 6, 2026; last updated July 6, 2026. https://supplychainattack.org/incident/malware-in-mjs-biginteger-b512xa
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