# CVE-2026-121967: Coder before 2.29.22, 2.34.13, 2.35.10, 2.36.8, 2.37.5, and 2.38.1 AI Gateway Path Traversal

Status: published. Published: 2026-11-04. Updated: 2026-11-04.

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.

## Remediation

- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: VulnCheck) — https://github.com/coder/coder/pull/30178

## Affected products and versions

- coder / coder (github.com/coder/coder/v2): ≥ 2.37.0; < 2.37.5 (affected, semver); 2.37.5 (unaffected, semver). Source: CNA: VulnCheck
- coder / coder (github.com/coder/coder/v2): ≥ 2.36.0; < 2.36.8 (affected, semver); 2.36.8 (unaffected, semver). Source: CNA: VulnCheck
- coder / coder (github.com/coder/coder/v2): ≥ 2.35.0; < 2.35.10 (affected, semver); 2.35.10 (unaffected, semver). Source: CNA: VulnCheck
- coder / coder (github.com/coder/coder/v2): ≥ 2.30.0; < 2.34.13 (affected, semver); 2.34.13 (unaffected, semver). Source: CNA: VulnCheck
- coder / coder (github.com/coder/coder/v2): ≥ 2.28.0; < 2.29.22 (affected, semver); 2.29.22 (unaffected, semver). Source: CNA: VulnCheck
- coder / coder (github.com/coder/coder/v2): ≥ 2.38.0; < 2.38.1 (affected, semver); 2.38.1 (unaffected, semver). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 2.3 (low); CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 4.9 (medium); CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:N; source: CNA: VulnCheck

- CVSS 4.0: 2.3 (low); CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X; source: NVD: disclosure@vulncheck.com

- CVSS 3.1: 4.9 (medium); CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:N; source: NVD: disclosure@vulncheck.com

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-22

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/coder/coder/security/advisories/GHSA-373r-678h-hjc6 (CNA: VulnCheck; vendor-advisory)

- https://github.com/coder/coder/pull/30178 (CNA: VulnCheck; patch, issue-tracking)

- https://www.vulncheck.com/advisories/coder-before-2.29.22-2.34.13-2.35.10-2.36.8-2.37.5-and-2.38.1-ai-gateway-path-traversal (CNA: VulnCheck; third-party-advisory)

- https://github.com/coder/coder/pull/30178 (disclosure@vulncheck.com)

- https://github.com/coder/coder/security/advisories/GHSA-373r-678h-hjc6 (disclosure@vulncheck.com)

- https://www.vulncheck.com/advisories/coder-before-2.29.22-2.34.13-2.35.10-2.36.8-2.37.5-and-2.38.1-ai-gateway-path-traversal (disclosure@vulncheck.com)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-121967; retrieved 2026-11-04; source updated 2026-11-04

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-121967; retrieved 2026-11-04; source updated 2026-11-04

Revision: 1ca2a5d97f3c2029aa6d44cafc157aec9011e302586326bb9e1ce2c3e2f775b1

Canonical: https://y2.dev/cve/CVE-2026-121967

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