Executive brief
npm cli, the JavaScript package manager, contains an insecure module loading mechanism that allows local attackers with low-privileged code execution to escalate their privileges and run arbitrary code. An attacker who gains initial access to a system can exploit this vulnerability to obtain the privileges of another user, potentially compromising the entire system or sensitive projects.
Technical details
This vulnerability is a local privilege escalation flaw rooted in improper permission assignment (CWE-732) in npm cli's module handling. The application loads modules from unsecured filesystem locations without proper validation, enabling a local attacker to inject malicious code. The attack requires prior low-privileged code execution on the target system and does not require user interaction. An attacker can leverage this vulnerability to execute arbitrary code with elevated privileges. This issue was initially flagged as a duplicate and the advisory was withdrawn on 2026-02-06, with the vendor stating the behavior was by design; however, the underlying privilege escalation risk remains in affected versions through at least v11.8.0.
Affected products
- npm npm cli All versions through 11.8.0
Timeline
- 2026-01-12: disclosed: Coordinated public release of ZDI advisory ZDI-26-043
- 2026-01-23: advisory: GHSA-3966-f6p6-2qr9 published
- 2026-02-06: other: GHSA advisory withdrawn as duplicate; vendor stated behavior was by design
- 2024-11-13: other: Vulnerability initially reported to vendor
- 2025-08-05: other: ZDI encouraged vendor reassessment