CVE-2021-32792: XSS vulnerability when using OIDCPreservePost On in mod_auth_openidc

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-07-26 · updated 2026-06-17
Weakness: CWE-79

Description

mod_auth_openidc is an authentication/authorization module for the Apache 2.x HTTP server that functions as an OpenID Connect Relying Party, authenticating users against an OpenID Connect Provider. In mod_auth_openidc before version 2.4.9, there is an XSS vulnerability in when using `OIDCPreservePost On`.

Affected products

Fedoraproject Fedora: 33, 34
OpenIDC mod_auth_openidc: before 2.4.9 — fixed in 2.4.9

How to fix

Upgrade to a fixed version: OpenIDC mod_auth_openidc 2.4.9. Check the vendor advisory for mitigations.

References

https://github.com/zmartzone/mod_auth_openidc/commit/00c315cb0c8ab77c67be4a2ac08a71a83ac58751
https://github.com/zmartzone/mod_auth_openidc/commit/55ea0a085290cd2c8cdfdd960a230cbc38ba8b56
https://github.com/zmartzone/mod_auth_openidc/releases/tag/v2.4.9
https://github.com/zmartzone/mod_auth_openidc/security/advisories/GHSA-458c-7pwg-3j7j
https://lists.debian.org/debian-lts-announce/2023/04/msg00034.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FZVF6BSJLRQZ7PFFR4X5JSU6KUJYNOCU/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QXAWKPT5LXZSUTFSJ6IWSZC7RMYYQXQD/
https://www.oracle.com/security-alerts/cpuapr2022.html
https://github.com/zmartzone/mod_auth_openidc/commit/00c315cb0c8ab77c67be4a2ac08a71a83ac58751
https://github.com/zmartzone/mod_auth_openidc/commit/55ea0a085290cd2c8cdfdd960a230cbc38ba8b56
https://github.com/zmartzone/mod_auth_openidc/releases/tag/v2.4.9
https://github.com/zmartzone/mod_auth_openidc/security/advisories/GHSA-458c-7pwg-3j7j

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