#VU112073 Input validation error in mod_auth_openidc - CVE-2025-3891

Vulnerability identifier: #VU112073

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2025-3891

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
mod_auth_openidc
Web applications / Modules and components for CMS

Vendor: ZmartZone IAM

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input when OIDCPreservePost is enabled in mod_auth_openidc. A remote attacker can send an HTTP POST request without a Content-Type header and crash the web server. 

Mitigation
Install updates from vendor's website.

Vulnerable software versions

mod_auth_openidc: 2.0.0 - 2.4.13.1

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External links
https://github.com/OpenIDC/mod_auth_openidc/security/advisories/GHSA-x7cf-8wgv-5j86
https://bugzilla.redhat.com/show_bug.cgi?id=2361633

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.