Debian DLA-3409-1 : libapache2-mod-auth-openidc - LTS security update

medium Nessus Plugin ID 174970

Synopsis

The remote Debian host is missing one or more security-related updates.

Description

The remote Debian 10 host has a package installed that is affected by multiple vulnerabilities as referenced in the dla-3409 advisory.

- A flaw was found in mod_auth_openidc before version 2.4.1. An open redirect issue exists in URLs with a slash and backslash at the beginning. (CVE-2019-20479)

- 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. When mod_auth_openidc versions prior to 2.4.9 are configured to use an unencrypted Redis cache (`OIDCCacheEncrypt off`, `OIDCSessionType server-cache`, `OIDCCacheType redis`), `mod_auth_openidc` wrongly performed argument interpolation before passing Redis requests to `hiredis`, which would perform it again and lead to an uncontrolled format string bug. Initial assessment shows that this bug does not appear to allow gaining arbitrary code execution, but can reliably provoke a denial of service by repeatedly crashing the Apache workers. This bug has been corrected in version 2.4.9 by performing argument interpolation only once, using the `hiredis` API. As a workaround, this vulnerability can be mitigated by setting `OIDCCacheEncrypt` to `on`, as cache keys are cryptographically hashed before use when this option is enabled. (CVE-2021-32785)

- 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-2021-32786)

- 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 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-2021-32791)

- 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, there is an XSS vulnerability in when using `OIDCPreservePost On`.
(CVE-2021-32792)

- mod_auth_openidc is an authentication and authorization module for the Apache 2.x HTTP server that implements the OpenID Connect Relying Party functionality. In versions 2.0.0 through 2.4.13.1, when `OIDCStripCookies` is set and a crafted cookie supplied, a NULL pointer dereference would occur, resulting in a segmentation fault. This could be used in a Denial-of-Service attack and thus presents an availability risk. Version 2.4.13.2 contains a patch for this issue. As a workaround, avoid using `OIDCStripCookies`. (CVE-2023-28625)

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

Solution

Upgrade the libapache2-mod-auth-openidc packages.

For Debian 10 buster, these problems have been fixed in version 2.3.10.2-1+deb10u2.

See Also

http://www.nessus.org/u?0371ebc9

Plugin Details

Severity: Medium

ID: 174970

File Name: debian_DLA-3409.nasl

Version: 1.1

Type: local

Agent: unix

Published: 5/1/2023

Updated: 5/3/2023

Supported Sensors: Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, 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-2021-32786

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

CVSS Score Source: CVE-2021-32792

Vulnerability Information

CPE: cpe:/o:debian:debian_linux:10.0, p-cpe:/a:debian:debian_linux:libapache2-mod-auth-openidc

Required KB Items: Host/local_checks_enabled, Host/Debian/release, Host/Debian/dpkg-l

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 4/30/2023

Vulnerability Publication Date: 2/20/2020

Reference Information

CVE: CVE-2019-20479, CVE-2021-32785, CVE-2021-32786, CVE-2021-32791, CVE-2021-32792, CVE-2023-28625