CVE-2021-39191
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.
Does this matter?
Lower severity and a low EPSS score (1.75%). Track it; it rarely justifies an emergency change on its own.
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.
- CVSS 3.1
- 6.1 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- EPSS
- 1.75% probability · 77th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-601
- Affected
- openidc/mod auth openidc · fedoraproject/fedora · debian/debian linux
- Source
- security-advisories@github.com
References
- https://github.com/zmartzone/mod_auth_openidc/commit/03e6bfb446f4e3f27c003d30d6a433e5dd8e2b3dPatch, Third Party Advisory
- https://github.com/zmartzone/mod_auth_openidc/issues/672Exploit
- https://github.com/zmartzone/mod_auth_openidc/releases/tag/v2.4.9.4Release Notes
- https://github.com/zmartzone/mod_auth_openidc/security/advisories/GHSA-2pgf-8h6h-gqg2Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2023/07/msg00020.htmlMailing List
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/32RGPW5LZDLDTB7MKZIGAHPSLFOUNWR5/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RHXO4O4G2UQS7X6OQJCVZKHZAQ7SAIFB/
- https://github.com/zmartzone/mod_auth_openidc/commit/03e6bfb446f4e3f27c003d30d6a433e5dd8e2b3dPatch, Third Party Advisory
- https://github.com/zmartzone/mod_auth_openidc/issues/672Exploit
- https://github.com/zmartzone/mod_auth_openidc/releases/tag/v2.4.9.4Release Notes
- https://github.com/zmartzone/mod_auth_openidc/security/advisories/GHSA-2pgf-8h6h-gqg2Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2023/07/msg00020.htmlMailing List
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/32RGPW5LZDLDTB7MKZIGAHPSLFOUNWR5/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RHXO4O4G2UQS7X6OQJCVZKHZAQ7SAIFB/
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.