CVE-2026-54789

mod_auth_openidc is an OpenID Certified authentication and authorization module for the Apache 2.x HTTP server that implements the OpenID Connect Relying Party functionality. Prior to 2.4.19.4, an out-of-bounds read and a one-byte out-of-bounds write exist in the state-cookie parser of `mod_auth_openidc`. The issue is fixed in version 2.4.19.4 by stopping the scan at the string terminator so a value-less token is rejected. No in-product workarounds are available. As a stop-gap, an upstream reverse proxy or WAF that rejects or normalizes malformed `Cookie` headers (tokens lacking `=`) can reduce exposure, but upgrading is the recommended remediation.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/OpenIDC/mod_auth_openidc/commit/8017478471cc071c49aa073c5c9be652a73a8630
https://github.com/OpenIDC/mod_auth_openidc/security/advisories/GHSA-vgr5-qcpp-x2pr
https://lists.debian.org/debian-lts-announce/2026/09/msg00003.html

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-21 16:17

Updated : 2026-09-02 19:17

NVD link : CVE-2026-54789

Mitre link : CVE-2026-54789

CVE.ORG link : CVE-2026-54789

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

CWE-787

Out-of-bounds Write

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