Improper Authentication in mod_auth_openidc - #VU159580
Published: November 6, 2026
Vulnerability identifier: #VU159580
CSH Severity: Medium
CVSS v4: 9.1 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-287
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows an unauthenticated remote attacker to bypass authentication and read or overwrite files in protected locations.
The vulnerability exists due to mod_auth_openidc reusing identities without authenticating the target when Apache sub-requests or internal redirects cross from locations configured with OIDCUnAuthAction pass or weaker authentication into separately protected locations. An unauthenticated remote attacker can trigger DirectoryIndex resolution or a WebDAV COPY to read protected content or overwrite protected files.
Affected software
mod_auth_openidc
Remediation
Install security update from vendor's website.
mod_auth_openidc - update to 2.4.20.4