CVE-2026-63478mediumCWE-22

CVE-2026-63478: medium-severity vulnerability in isomorphic-git

isomorphic-git: Path traversal via a ".." tree-entry name writes files outside the working directory on clone/checkout

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 5.3epss 0.3%
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.
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N
Affected products
isomorphic-git · isomorphic-git
Related CVEs — isomorphic-git

In the same product, most dangerous first.

CVE-2026-63395HIGHisomorphic-git: Arbitrary file write outside the working tree via a directory symlink during checkout (potential RCE)EPSS 0.7%CVE-2026-89011HIGHisomorphic-git < 1.42.0 Prototype Pollution via getRemoteInfoEPSS 0.4%CVE-2026-63475MEDIUMisomorphic-git: Circular symbolic references cause non-terminating resolution (DoS)EPSS 0.4%CVE-2026-63476MEDIUMisomorphic-git: Unbounded memory allocation from attacker-controlled delta target size (DoS)EPSS 0.3%