CVE-2021-32786

Publication date 22 July 2021

Last updated 24 July 2024

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

6.1 · Medium

Score breakdown

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.

Status

Package Ubuntu Release Status
libapache2-mod-auth-openidc 24.10 oracular
Not affected
24.04 LTS noble
Not affected
23.10 mantic
Not affected
23.04 lunar
Not affected
22.10 kinetic
Not affected
22.04 LTS jammy
Not affected
21.10 impish
Not affected
21.04 hirsute Ignored end of life
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Vulnerable
14.04 LTS trusty Not in release

Severity score breakdown

Parameter Value
Base score 6.1 · Medium
Attack vector Network
Attack complexity Low
Privileges required None
User interaction Required
Scope Changed
Confidentiality Low
Integrity impact Low
Availability impact None
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N