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CVE-2026-54789 (GCVE-0-2026-54789)

Vulnerability from cvelistv5 – Published: 2026-08-21 16:13 – Updated: 2026-09-02 19:06
VLAI
Title
mod_auth_openidc has out-of-bounds read and write in state cookie parsing
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-21 17:23 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
OpenIDC mod_auth_openidc Affected: < 2.4.19.4
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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