SUSE SLES15 Security Update : apache2-mod_auth_openidc (SUSE-SU-2021:3020-1)

medium Nessus Plugin ID 153248

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Synopsis

The remote SUSE host is missing one or more security updates.

Description

The remote SUSE Linux SLES15 host has a package installed that is affected by multiple vulnerabilities as referenced in the SUSE-SU-2021:3020-1 advisory.

- 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)

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 apache2-mod_auth_openidc package.

See Also

https://bugzilla.suse.com/1188638

https://bugzilla.suse.com/1188639

https://bugzilla.suse.com/1188848

https://bugzilla.suse.com/1188849

https://www.suse.com/security/cve/CVE-2021-32785

https://www.suse.com/security/cve/CVE-2021-32786

https://www.suse.com/security/cve/CVE-2021-32791

https://www.suse.com/security/cve/CVE-2021-32792

http://www.nessus.org/u?cd988498

Plugin Details

Severity: Medium

ID: 153248

File Name: suse_SU-2021-3020-1.nasl

Version: 1.4

Type: local

Agent: unix

Published: 9/14/2021

Updated: 7/14/2023

Supported Sensors: Agentless Assessment, Continuous Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, 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:novell:suse_linux:15, p-cpe:/a:novell:suse_linux:apache2-mod_auth_openidc

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

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 9/13/2021

Vulnerability Publication Date: 7/22/2021

Reference Information

CVE: CVE-2021-32785, CVE-2021-32786, CVE-2021-32791, CVE-2021-32792

SuSE: SUSE-SU-2021:3020-1