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CVE-2026-63478

5.3 mediumEPSS 0.3%

Medium (5.3). EPSS 0.3% estimated probability of exploitation activity in the next 30 days.

On this page
isomorphic-git is a pure JavaScript implementation of Git for Node.js and browsers. Prior to 1.38.6, isomorphic-git's tree parser in src/models/GitTree.js accepts a standalone .. tree-entry name because it rejects only path separators. During clone or checkout from a malicious or man-in-the-middle-controlled non-GitHub remote, nested .. entries can escape the working-tree root and write files at attacker-selected parent paths on any host-backed fs provider. The arbitrary file write can overwrite startup or configuration files and lead to code execution. GitHub-hosted trees are not a direct source because GitHub rejects .. entries during repository integrity checks. This issue is fixed in version 1.38.6.

Severity

CVSS 3.1

5.3 medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N
EPSS
0.3% estimated probability of exploitation activity in the next 30 days; 22nd percentile. Scored 2026-11-04. A forecast for this CVE across the internet, not for your own systems.
CWE
CWE-22 Improper Limitation of a Pathname to a Restricted Directory (Path traversal)
OWASP Top 10
A01:2025 Broken Access Control
Published
Modified
Record from
the NVD, synced

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Versions

From the CNA's record in the CVE List.

ProductAffected
isomorphic-git< 1.38.6

Attack patterns (CAPEC)

  • CAPEC-64 Using Slashes and URL Encoding Combined to Bypass Validation Logic Likelihood: High · Severity: High
  • CAPEC-76 Manipulating Web Input to File System Calls Likelihood: High · Severity: Very High
  • CAPEC-78 Using Escaped Slashes in Alternate Encoding Likelihood: High · Severity: High
  • CAPEC-79 Using Slashes in Alternate Encoding Likelihood: High · Severity: High
  • CAPEC-126 Path Traversal Likelihood: High · Severity: Very High

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.

References

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