Alibaba Cloud Linux 3 : 0135: mod_auth_openidc:2.3 (ALINUX3-SA-2022:0135)

medium Nessus Plugin ID 236723

Synopsis

The remote Alibaba Cloud Linux host is missing one or more security updates.

Description

The remote Alibaba Cloud Linux 3 host has packages installed that are affected by multiple vulnerabilities as referenced in the ALINUX3-SA-2022:0135 advisory.

Package updates are available for Alibaba Cloud Linux 3 that fix the following vulnerabilities:

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.

CVE-2021-32791:
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 mod_auth_openidc before version 2.4.9, the AES GCM encryption in mod_auth_openidc uses a static IV and AAD. It is important to fix because this creates a static nonce and since aes-gcm is a stream cipher, this can lead to known cryptographic issues, since the same key is being reused. From 2.4.9 onwards this has been patched to use dynamic values through usage of cjose AES encryption routines.

CVE-2021-32792:
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 mod_auth_openidc before version 2.4.9, there is an XSS vulnerability in when using `OIDCPreservePost On`.

CVE-2021-39191:
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.

Tenable has extracted the preceding description block directly from the Alibaba Cloud Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Update the affected mod_auth_openidc, mod_auth_openidc-debuginfo and / or mod_auth_openidc-debugsource packages.

Plugin Details

Severity: Medium

ID: 236723

File Name: alinux3_sa_2022-0135.nasl

Version: 1.1

Type: local

Family: Alibaba Cloud Linux Local Security Checks

Published: 5/14/2025

Updated: 5/14/2025

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.8

CVSS v2

Risk Factor: Medium

Base Score: 5.8

Temporal Score: 4.5

Vector: CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:N

CVSS Score Source: CVE-2021-39191

CVSS v3

Risk Factor: Medium

Base Score: 6.1

Temporal Score: 5.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:mod_auth_openidc-debuginfo, p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:mod_auth_openidc-debugsource, p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:mod_auth_openidc, cpe:/o:alibabacloud:alibaba_cloud_linux_3

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/Alibaba/release, Host/Alibaba/rpm-list

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 7/21/2022

Vulnerability Publication Date: 7/22/2021

Reference Information

CVE: CVE-2021-32786, CVE-2021-32791, CVE-2021-32792, CVE-2021-39191

Detections

Analytics