{"id":"CVE-2026-63478","published":"2026-11-03T20:18:16.240","lastModified":"2026-11-03T20:18:16.367","description":"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.","cvssScore":5.3,"cvssSeverity":"MEDIUM","cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N","cwes":["CWE-22"],"vendors":[],"products":[],"references":[{"url":"https://github.com/isomorphic-git/isomorphic-git/commit/823843d1cd19182df79bc907c767f5bcecb39a0b","tags":[]},{"url":"https://github.com/isomorphic-git/isomorphic-git/pull/2370","tags":[]},{"url":"https://github.com/isomorphic-git/isomorphic-git/releases/tag/v1.38.6","tags":[]},{"url":"https://github.com/isomorphic-git/isomorphic-git/security/advisories/GHSA-cw2g-2vwq-88w6","tags":[]}],"exploitRefs":[{"url":"https://github.com/isomorphic-git/isomorphic-git/commit/823843d1cd19182df79bc907c767f5bcecb39a0b","tags":[]},{"url":"https://github.com/isomorphic-git/isomorphic-git/pull/2370","tags":[]},{"url":"https://github.com/isomorphic-git/isomorphic-git/releases/tag/v1.38.6","tags":[]},{"url":"https://github.com/isomorphic-git/isomorphic-git/security/advisories/GHSA-cw2g-2vwq-88w6","tags":[]}],"hasPoc":true,"ai":null}