pnpm: Binary ZIP extraction allows arbitrary file write via path traversal (Zip Slip) (CVE-2026-23888)
Description
A path traversal vulnerability in pnpm's binary fetcher prior to version 10.28.1 allows malicious ZIP packages to write files outside the intended extraction directory. This can occur via crafted ZIP entries with '../' or absolute paths, or by manipulating the BinaryResolution.prefix field. The vulnerability can lead to overwriting sensitive files and potentially remote code execution. The issue is patched in version 10.28.1.
CVSS v3.1
Score 6.5medium
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
pnpm versions prior to 10.28.1 contain a path traversal vulnerability in the binary fetcher component. The flaw arises from improper validation of ZIP archive entries and the BinaryResolution.prefix field, allowing crafted packages to escape the extraction root directory and write arbitrary files on the filesystem. This is due to AdmZip's extractAllTo method not sanitizing paths and concatenation of an unvalidated prefix into the extraction path. The vulnerability affects users installing packages with binary assets, those configuring custom Node.js binary locations, and CI/CD pipelines auto-installing binaries. The vulnerability is fixed in pnpm version 10.28.1.
Potential Impact
An attacker can craft malicious packages that, when installed, write files outside the intended directory, potentially overwriting configuration files, scripts, or other sensitive files. This can lead to remote code execution (RCE) if critical files are replaced or modified. The vulnerability affects the integrity of the system and can compromise environments where pnpm is used to install binary assets.
Mitigation Recommendations
A patch is available in pnpm version 10.28.1 that fixes the path traversal vulnerability. Users should upgrade to version 10.28.1 or later to remediate this issue. No additional mitigation is required if the update is applied.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- BREW-pnpm-CVE-2026-23888
- Osv Schema Version
- 1.7.3
- Ecosystems
- ["Homebrew"]
- Cvss Version
- 3.1
Patch Information
Threat ID: 6ac2c0b22cdf04f656523913
Added to database: 10/04/2026, 21:10:10 UTC
Last enriched: 10/04/2026, 21:17:22 UTC
Last updated: 10/04/2026, 21:17:22 UTC
Views: 2
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