CVE-2026-37236

Aliases:DEBIAN-CVE-2026-37236UBUNTU-CVE-2026-37236openSUSE-SU-2026:11669-1
Advisory lineage Upstream: 0 Downstream: 13
Deferred
Published: 28 Aug 2026, 00:00
Last modified:02 Sept 2026, 18:14

Vulnerability Summary

Overall Risk (default)
high
70/100
CVSS Score
9.8 CRITICAL
v3.1 (cve.org)
EPSS Score
0.44% LOW
0% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

28 Aug 2026, 00:00
Published
Vulnerability first disclosed
02 Sept 2026, 18:14
Last Modified
Vulnerability information updated

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.

CVSS Metrics

  • v3.1•CRITICAL•Score: 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Trends

Current EPSS score: 0.44%• Percentile: 38%

Techniques & Countermeasures

  • CWE-639•Authorization Bypass Through User-Controlled Key

    The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.

Affected Systems

  • debian•golang-github-grpc-ecosystem-grpc-gateway

    all | all | all | all | < 2.30.0-1

  • ubuntu•golang-github-grpc-ecosystem-grpc-gateway

    all | all | all | all | all

  • opensuse•helm3&distro=openSUSE Tumbleweed

    < 3.21.3-7.1

References (7)