CVE-2021-32786
published 2021-07-22CVE-2021-32786: mod_auth_openidc is an authentication/authorization module for the Apache 2.x HTTP server that functions as an OpenID Connect Relying Party, authenticating…
PriorityP431medium6.1CVSS 3.1
AVNACLPRNUIRSCCLILAN
EPSS
2.36%
82.0th percentile
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, `oidc_validate_redirect_url()` does not parse URLs the same way as most browsers do. As a result, this function can be bypassed and leads to an Open Redirect vulnerability in the logout functionality. This bug has been fixed in version 2.4.9 by replacing any backslash of the URL to redirect with slashes to address a particular breaking change between the different specifications (RFC2396 / RFC3986 and WHATWG). As a workaround, this vulnerability can be mitigated by configuring `mod_auth_openidc` to only allow redirection whose destination matches a given regular expression.
Affected
8 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | libapache2-mod-auth-openidc | < libapache2-mod-auth-openidc 2.4.9-1 (bookworm) | libapache2-mod-auth-openidc 2.4.9-1 (bookworm) |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| msrc | cbl2_httpd_2.4.52-1_on_cbl_mariner_2.0 | — | — |
| msrc | cbl_mariner_2.0_arm | — | — |
| msrc | cbl_mariner_2.0_x64 | — | — |
| openidc | mod_auth_openidc | < 2.4.9 | 2.4.9 |
| zmartzone | mod_auth_openidc | < 2.4.9 | 2.4.9 |
CVSS provenance
nvdv3.16.1MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
nvdv2.05.8MEDIUMAV:N/AC:M/Au:N/C:P/I:P/A:N
osv6.1MEDIUM
vendor_msrc6.1MEDIUM
vendor_debian4.7MEDIUM
vendor_redhat4.7MEDIUM
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OSV
CVE-2021-32786: mod_auth_openidc is an authentication/authorization module for the Apache 2
osv·2021-07-22·CVSS 6.1
CVE-2021-32786 [MEDIUM] CVE-2021-32786: mod_auth_openidc is an authentication/authorization module for the Apache 2
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, `oidc_validate_redirect_url()` does not parse URLs the same way as most browsers do. As a result, this function can be bypassed and leads to an Open Redirect vulnerability in the logout functionality. This bug has been fixed in version 2.4.9 by replacing any backslash of the URL to redirect with slashes to address a particular breaking change between the different specifications (RFC2396 / RFC3986 and WHATWG). As a workaround, this vulnerability can be mitigated by configuring `mod_auth_openidc` to only allow redirection whose destination matches a given regular expre
Red Hat
mod_auth_openidc: open redirect in oidc_validate_redirect_url()
vendor_redhat·2021-07-22·CVSS 4.7
CVE-2021-32786 [MEDIUM] CWE-601 mod_auth_openidc: open redirect in oidc_validate_redirect_url()
mod_auth_openidc: open redirect in oidc_validate_redirect_url()
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, `oidc_validate_redirect_url()` does not parse URLs the same way as most browsers do. As a result, this function can be bypassed and leads to an Open Redirect vulnerability in the logout functionality. This bug has been fixed in version 2.4.9 by replacing any backslash of the URL to redirect with slashes to address a particular breaking change between the different specifications (RFC2396 / RFC3986 and WHATWG). As a workaround, this vulnerability can be mitigated by configuring `mod_auth_openidc` to only
Microsoft
Open Redirect in oidc_validate_redirect_url()
vendor_msrc·2021-07-13·CVSS 6.1
CVE-2021-32786 [MEDIUM] CWE-601 Open Redirect in oidc_validate_redirect_url()
Open Redirect in oidc_validate_redirect_url()
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
GitHub_M: GitHub_M
Customer Action Required: Yes
Remediation: CBL-Mariner Releases
Reference: https://learn.mic
Debian
CVE-2021-32786: libapache2-mod-auth-openidc - mod_auth_openidc is an authentication/authorization module for the Apache 2.x HT...
vendor_debian·2021·CVSS 4.7
CVE-2021-32786 [MEDIUM] CVE-2021-32786: libapache2-mod-auth-openidc - mod_auth_openidc is an authentication/authorization module for the Apache 2.x HT...
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, `oidc_validate_redirect_url()` does not parse URLs the same way as most browsers do. As a result, this function can be bypassed and leads to an Open Redirect vulnerability in the logout functionality. This bug has been fixed in version 2.4.9 by replacing any backslash of the URL to redirect with slashes to address a particular breaking change between the different specifications (RFC2396 / RFC3986 and WHATWG). As a workaround, this vulnerability can be mitigated by configuring `mod_auth_openidc` to only allow redirection whose destination matches a given regular expre
No detection rules found.
No public exploits indexed.
https://daniel.haxx.se/blog/2017/01/30/one-url-standard-please/https://github.com/zmartzone/mod_auth_openidc/commit/3a115484eb927bc6daa5737dd84f88ff4bbc5544https://github.com/zmartzone/mod_auth_openidc/releases/tag/v2.4.9https://github.com/zmartzone/mod_auth_openidc/security/advisories/GHSA-xm4c-5wm5-jqv7https://lists.debian.org/debian-lts-announce/2023/04/msg00034.htmlhttps://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://security.netapp.com/advisory/ntap-20210902-0001/https://www.oracle.com/security-alerts/cpuapr2022.htmlhttps://daniel.haxx.se/blog/2017/01/30/one-url-standard-please/https://github.com/zmartzone/mod_auth_openidc/commit/3a115484eb927bc6daa5737dd84f88ff4bbc5544https://github.com/zmartzone/mod_auth_openidc/releases/tag/v2.4.9https://github.com/zmartzone/mod_auth_openidc/security/advisories/GHSA-xm4c-5wm5-jqv7https://lists.debian.org/debian-lts-announce/2023/04/msg00034.htmlhttps://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://security.netapp.com/advisory/ntap-20210902-0001/https://www.oracle.com/security-alerts/cpuapr2022.html
2021-07-22
Published