CVE-2026-63475
Dashboard / Vulnerabilities / CVE-2026-63475
Summary: isomorphic-git: Circular symbolic references cause non-terminating resolution (DoS)
Details: isomorphic-git is a pure JavaScript implementation of Git for Node.js and browsers. Prior to 1.38.6, isomorphic-git persists server-supplied circular symref= capabilities through updateRemoteRefs, and GitRefManager.resolve() follows the resulting loose symbolic references without a default depth limit or cycle detection. After a clone from a malicious or man-in-the-middle-controlled remote, operations such as log, status, checkout, and branch that resolve refs/remotes/origin/a or refs/remotes/origin/b do not terminate. The circular references remain on disk, leaving the repository unusable for the application and causing a persistent denial of service. This issue is fixed in version 1.38.6.
References: https://github.com/isomorphic-git/isomorphic-git/releases/tag/v1.38.6, https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63475.json, https://github.com/isomorphic-git/isomorphic-git/security/advisories/GHSA-96wc-2m84-2cj7, https://nvd.nist.gov/vuln/detail/CVE-2026-63475, https://github.com/isomorphic-git/isomorphic-git/commit/823843d1cd19182df79bc907c767f5bcecb39a0b, https://github.com/isomorphic-git/isomorphic-git/pull/2370
Affected packages
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