Path Traversal in Coder
CVE-2026-121967
Coder 2.28.0 before 2.29.22, 2.30.0 before 2.34.13, 2.35.0 before 2.35.10, 2.36.0 before 2.36.8, 2.37.0 before 2.37.5, and 2.38.0 before 2.38.1 contains a path traversal vulnerability in the AI Gateway passthrough router, which forwards percent-encoded dot segments upstream without rejecting them. Authenticated users can send paths such as %2e%2e or ..%2F under allowlisted prefixes to reach unintended provider endpoints using the deployment's centrally managed provider key.
Vulnerability class: Path Traversal (Directory Traversal)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/coder/coder/security/advisories/GHSA-373r-678h-hjc6 (vendor-advisory)
- github.com/coder/coder/pull/30178 (issue-tracking, patch)
- www.vulncheck.com/advisories/coder-before-2.29.22-2.34.13-2.35.10-2.36.8-2.37.5… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-121967?
- CVE-2026-121967 is a medium-severity vulnerability in Coder, classified under Path Traversal. CVSS score: 4.9/10. Published 2026-11-04.
- How severe is CVE-2026-121967?
- Medium severity. CVSS v3 base score is 4.9 out of 10.