Input validation error in mod_auth_openidc - #VU142420
Published: August 13, 2026
Vulnerability identifier: #VU142420
CSH Severity: High
CVSS v4: 8.8 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to inject trusted identity headers into backend requests.
The vulnerability exists due to improper input validation in header scrubbing logic when handling unauthenticated request paths. A remote attacker can send crafted OIDC-related headers to inject trusted identity headers into backend requests.
Exploitation depends on the backend application trusting these headers as authenticated identity claims on affected paths.
Affected software
mod_auth_openidc
Remediation
Install security update from vendor's website.
mod_auth_openidc - update to 2.4.20.1