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DoS when sending empty Content-Type header with OIDCPreservePost On

Moderate
zandbelt published GHSA-x7cf-8wgv-5j86 May 7, 2025

Package

mod_auth_openidc

Affected versions

>= 2.0.0 <= 2.4.13.1

Patched versions

>= 2.4.13.2

Description

Impact

An unauthenticated attacker can crash the Apache httpd process by sending a POST request without a Content-Type header when OIDCPreservePost is enabled in mod_auth_openidc. This leads to denial of service.

Patches

Users should upgrade to a version of mod_auth_openidc greater than 2.4.13.1.

Workarounds

There are no workarounds other than disabling OIDCPreservePost.

References

https://bugzilla.redhat.com/show_bug.cgi?id=2361633

Severity

Moderate

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

CVE ID

CVE-2025-3891

Weaknesses

Uncaught Exception

An exception is thrown from a function, but it is not caught. Learn more on MITRE.