CVE Vulnerability

CVE-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 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.

5.8 /10

CVSS v2.0 :

V3 Legend

Vector :

Exploitability : 8.6 / Impact : 4.9

Attack Vector

Attack Complexity

Privileges Required

User Interaction

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact NONE

Scope

6.1 /10

CVSS v3.0 : MEDIUM

V3 Legend

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References
Link Resource
https://daniel.haxx.se/blog/2017/01/30/one-url-standard-please/ Exploit Third Party Advisory
https://github.com/zmartzone/mod_auth_openidc/releases/tag/v2.4.9 Release Notes Third Party Advisory
https://github.com/zmartzone/mod_auth_openidc/commit/3a115484eb927bc6daa5737dd84f88ff4bbc5544 Patch Third Party Advisory
https://github.com/zmartzone/mod_auth_openidc/security/advisories/GHSA-xm4c-5wm5-jqv7 Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/QXAWKPT5LXZSUTFSJ6IWSZC7RMYYQXQD/ Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/FZVF6BSJLRQZ7PFFR4X5JSU6KUJYNOCU/ Mailing List Third Party Advisory
https://security.netapp.com/advisory/ntap-20210902-0001/ Third Party Advisory
https://www.oracle.com/security-alerts/cpuapr2022.html Patch Third Party Advisory
Configurations

Configuration 1

cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
Information

Published : 2021-07-22 10:15

Updated : 2022-05-10 06:02

NVD link : CVE-2021-32786

Mitre link : CVE-2021-32786

Products Affected
No products.
CWE
CWE-601

URL Redirection to Untrusted Site ('Open Redirect')