CVE-2026-37236: grpc-gateway v2.28.0 is vulnerable to Incorrect Access Control. The application processes the X-HTTP-Method-Override header in ServeMux.ServeHTTP without restricting allowed methods. When a POST request with Content-Type application/x-www-form-urlencoded includes this header, the request method is rewritten to an arbitrary attacker-supplied value before routing. This allows bypassing method-based access controls enforced by upstream proxies or WAFs.
Overview
- Severity
- Medium (CVSS 5.3)
- CVSS Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:U
- Exploit Status
- Not Exploited
- Patch Tuesday
- 2026-Aug
- Released
- 2026-09-02
- EPSS Score
- 0.18% (percentile: 7.2%)
Affected Products (9)
Other
- 21688-17084
- 21768-17084
- 21744-17084
- 21743-17084
- 21682-17084
- 21771-17084
- 21745-17084
- 21769-17084
- 21770-17084
Revision History
- 2026-09-02: Information published.