CVE-2026-23888CWE-22CWE-23CWE-426

pnpm: Binary ZIP extraction allows arbitrary file write via path traversal (Zip Slip)

Medium · published January 26, 2026

CVSS v3.1
6.5
EPSS
0%
Percentile
38.4
In the wild
Unconfirmed
What it is

pnpm is a package manager. Prior to version 10.28.1, a path traversal vulnerability in pnpm's binary fetcher allows malicious packages to write files outside the intended extraction directory. The vulnerability has two attack vectors: (1) Malicious ZIP entries containing `../` or absolute paths that escape the extraction root via AdmZip's `extractAllTo`, and (2) The `BinaryResolution.prefix` field is concatenated into the extraction path without validation, allowing a crafted prefix like `../../evil` to redirect extracted files outside `targetDir`. The issue impacts all pnpm users who install packages with binary assets, users who configure custom Node.js binary locations and CI/CD pipelines that auto-install binary dependencies. It can lead to overwriting config files, scripts, or other sensitive files leading to RCE. Version 10.28.1 contains a patch.

The record
Technical detail
CVSS v3.1
6.5 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00454 · 38.4th percentile
Weaknesses
CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal'); CWE-23 · Relative Path Traversal; CWE-426 · Untrusted Search Path
Published
2026-01-26T21:37Z
EPSS history
Timeline
  • 26 JAN 21:37Z
    pnpm: Binary ZIP extraction allows arbitrary file write via path traversal (Zip Slip)
    cvelistv5