Vulnerability in Coder
CVE-2026-118687
Coder before 2.29.21, 2.30.0 before 2.34.12, 2.35.0 before 2.35.9, 2.36.0 before 2.36.7, and 2.37.0 before 2.37.4 does not validate the audience claim of GCE instance-identity JWTs at the POST /api/v2/workspaceagents/google-instance-identity endpoint. Attackers who obtain an unexpired format=full identity token minted for another relying party can replay it to obtain that workspace agent's session token, which remains valid until the workspace's next build.
Published .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/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-24vh-q7rg-243w (vendor-advisory)
- www.vulncheck.com/advisories/coder-before-2.29.21-2.34.12-2.35.9-2.36.7-and-2.3… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-118687?
- CVE-2026-118687 is a medium-severity vulnerability in Coder, classified under Unintended Proxy or Intermediary (Confused Deputy). CVSS score: 6.5/10. Published 2026-10-28.
- How severe is CVE-2026-118687?
- Medium severity. CVSS v3 base score is 6.5 out of 10.