CVE-2026-37236

critical

Description

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.

References

https://s00me00ne.com/cve/cve-2026-37236/

https://github.com/grpc-ecosystem/grpc-gateway/commit/72123cd4f32545f6e1376873f412dcdcbcf29acc

https://github.com/grpc-ecosystem/grpc-gateway

Details

Source: Mitre, NVD

Published: 2026-08-28

Updated: 2026-08-28

Risk Information

CVSS v2

Base Score: 7.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

Severity: High

CVSS v3

Base Score: 9.8

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Severity: Critical

EPSS

EPSS: 0.00176