SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-23889

Prior to version 10.28.1, a path traversal vulnerability in pnpm's tarball extraction allows malicious packages to write files outside the package directory on Windows.

MEDIUM 6.5EPSS 0.48%

Does this matter?

Lower severity and a low EPSS score (0.48%). Track it; it rarely justifies an emergency change on its own.

Description

pnpm is a package manager. Prior to version 10.28.1, a path traversal vulnerability in pnpm's tarball extraction allows malicious packages to write files outside the package directory on Windows. The path normalization only checks for `./` but not `.\`. On Windows, backslashes are directory separators, enabling path traversal. This vulnerability is Windows-only. This issue impacts Windows pnpm users and Windows CI/CD pipelines (GitHub Actions Windows runners, Azure DevOps). It can lead to overwriting `.npmrc`, build configs, or other files. Version 10.28.1 contains a patch.

CVSS 3.1
6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
EPSS
0.48% probability · 41th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-22
Affected
pnpm/pnpm
Source
security-advisories@github.com
EPSS trend
0%3%5%27 October 2026: 0.48%27 October 202627 October 2026

EPSS 0.5% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.