CVE-2021-32791

Hardcoded static IV and AAD with a reused key in AES GCM encryption in mod_auth_openidc

Description

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.

Categories

5.9
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.23%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org
Affected: zmartzone mod_auth_openidc
Published at:
Updated at:

References

Link Tags
https://github.com/zmartzone/mod_auth_openidc/releases/tag/v2.4.9 release notes third party advisory
https://github.com/zmartzone/mod_auth_openidc/security/advisories/GHSA-px3c-6x7j-3r9r third party advisory patch
https://github.com/zmartzone/mod_auth_openidc/commit/375407c16c61a70b56fdbe13b0d2c8f11398e92c third party advisory patch
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FZVF6BSJLRQZ7PFFR4X5JSU6KUJYNOCU/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QXAWKPT5LXZSUTFSJ6IWSZC7RMYYQXQD/ vendor advisory
https://www.oracle.com/security-alerts/cpuapr2022.html third party advisory patch
https://lists.debian.org/debian-lts-announce/2023/04/msg00034.html mailing list

Frequently Asked Questions

What is the severity of CVE-2021-32791?
CVE-2021-32791 has been scored as a medium severity vulnerability.
How to fix CVE-2021-32791?
To fix CVE-2021-32791, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-32791 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-32791 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-32791?
CVE-2021-32791 affects zmartzone mod_auth_openidc.
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