CVE Vulnerabilities

CVE-2021-32637

Improper Authentication

Published: May 28, 2021 | Modified: Jun 09, 2021
CVSS 3.x
10
CRITICAL
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
CVSS 2.x
7.5 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P
RedHat/V2
RedHat/V3
Ubuntu

Authelia is a a single sign-on multi-factor portal for web apps. This affects uses who are using nginx ngx_http_auth_request_module with Authelia, it allows a malicious individual who crafts a malformed HTTP request to bypass the authentication mechanism. It additionally could theoretically affect other proxy servers, but all of the ones we officially support except nginx do not allow malformed URI paths. The problem is rectified entirely in v4.29.3. As this patch is relatively straightforward we can back port this to any version upon request. Alternatively we are supplying a git patch to 4.25.1 which should be relatively straightforward to apply to any version, the git patches for specific versions can be found in the references. The most relevant workaround is upgrading. You can also add a block which fails requests that contains a malformed URI in the internal location block.

Weakness

When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

Affected Software

Name Vendor Start Version End Version
Authelia Authelia 4.0.0 (including) 4.25.1 (excluding)
Authelia Authelia 4.26.0 (including) 4.29.3 (excluding)

Potential Mitigations

References