CVE-2021-39191
4.7 MEDIUMmod_auth_openidc is an authentication/authorization module for the Apache 2.x HTTP server that functions as an OpenID Connect Relying Par...
Published: 2021-09-03 · Last updated: 2026-06-17
Severity and scoring
- CVSS
- 4.7 MEDIUM
- Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N
- CWE
- CWE-601
Affected products
| Vendor | Product |
|---|---|
| debian | debian_linux, fedora, mod_auth_openidc |
| fedoraproject | debian_linux, fedora, mod_auth_openidc |
| openidc | debian_linux, fedora, mod_auth_openidc |
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 versions prior to 2.4.9.4, the 3rd-party init SSO functionality of mod_auth_openidc was reported to be vulnerable to an open redirect attack by supplying a crafted URL in the `target_link_uri` parameter. A patch in version 2.4.9.4 made it so that the `OIDCRedirectURLsAllowed` setting must be applied to the `target_link_uri` parameter. There are no known workarounds aside from upgrading to a patched version.
Source: NVD
References
- [NVD]https://nvd.nist.gov/vuln/detail/CVE-2021-39191
- [Patch]https://github.com/zmartzone/mod_auth_openidc/commit/03e6bfb446f4e3f27c003d30d6a433e5dd8e2b3d
- [Exploit reference]https://github.com/zmartzone/mod_auth_openidc/issues/672
- [Other]https://github.com/zmartzone/mod_auth_openidc/releases/tag/v2.4.9.4
- [Vendor advisory]https://github.com/zmartzone/mod_auth_openidc/security/advisories/GHSA-2pgf-8h6h-gqg2
- [Other]https://lists.debian.org/debian-lts-announce/2023/07/msg00020.html
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/32RGPW5LZDLDTB7MKZIGAHPSLFOUNWR5/
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RHXO4O4G2UQS7X6OQJCVZKHZAQ7SAIFB/
- [Patch]https://github.com/zmartzone/mod_auth_openidc/commit/03e6bfb446f4e3f27c003d30d6a433e5dd8e2b3d
- [Exploit reference]https://github.com/zmartzone/mod_auth_openidc/issues/672
- [Other]https://github.com/zmartzone/mod_auth_openidc/releases/tag/v2.4.9.4
- [Vendor advisory]https://github.com/zmartzone/mod_auth_openidc/security/advisories/GHSA-2pgf-8h6h-gqg2
- [Other]https://lists.debian.org/debian-lts-announce/2023/07/msg00020.html
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/32RGPW5LZDLDTB7MKZIGAHPSLFOUNWR5/
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RHXO4O4G2UQS7X6OQJCVZKHZAQ7SAIFB/
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