CVE-2021-32791
published 2021-07-26CVE-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…
PriorityP430medium5.9CVSS 3.1
AVNACHPRNUINSUCHINAN
EPSS
1.50%
71.4th percentile
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.
Affected
8 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | libapache2-mod-auth-openidc | < libapache2-mod-auth-openidc 2.4.9-1 (bookworm) | libapache2-mod-auth-openidc 2.4.9-1 (bookworm) |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| msrc | cbl2_httpd_2.4.52-1_on_cbl_mariner_2.0 | — | — |
| msrc | cbl_mariner_2.0_arm | — | — |
| msrc | cbl_mariner_2.0_x64 | — | — |
| openidc | mod_auth_openidc | < 2.4.9 | 2.4.9 |
| zmartzone | mod_auth_openidc | < 2.4.9 | 2.4.9 |
CVSS provenance
nvdv3.15.9MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
nvdv2.04.3MEDIUMAV:N/AC:M/Au:N/C:P/I:N/A:N
osv5.9MEDIUM
vendor_debian5.9MEDIUM
vendor_msrc5.9MEDIUM
vendor_redhat5.9MEDIUM
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Red Hat
mod_auth_openidc: hardcoded static IV and AAD with a reused key in AES GCM encryption
vendor_redhat·2021-07-24·CVSS 5.9
CVE-2021-32791 [MEDIUM] CWE-330 mod_auth_openidc: hardcoded static IV and AAD with a reused key in AES GCM encryption
mod_auth_openidc: hardcoded static IV and AAD with a reused key in AES GCM encryption
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.
A flaw was found in mod_auth_openidc. The AES GCM encryption uses a static IV and AAD which could lead to other cr
Microsoft
Hardcoded static IV and AAD with a reused key in AES GCM encryption in mod_auth_openidc
vendor_msrc·2021-07-13·CVSS 5.9
CVE-2021-32791 [MEDIUM] CWE-323 Hardcoded static IV and AAD with a reused key in AES GCM encryption in mod_auth_openidc
Hardcoded static IV and AAD with a reused key in AES GCM encryption in mod_auth_openidc
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
GitHub_M: GitHub_M
Customer Action Required: Yes
Remediation: CBL-Mari
Debian
CVE-2021-32791: libapache2-mod-auth-openidc - mod_auth_openidc is an authentication/authorization module for the Apache 2.x HT...
vendor_debian·2021·CVSS 5.9
CVE-2021-32791 [MEDIUM] CVE-2021-32791: libapache2-mod-auth-openidc - mod_auth_openidc is an authentication/authorization module for the Apache 2.x HT...
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.
Scope: local
bookworm: resolved (fixed in 2.4.9-1)
bullseye: resolved (fixed in 2.4.9-1)
forky: resolved (fixed in 2.4.9-1)
sid: resolved (fixed in 2.4.9-1)
trixie: resolved (fixed in 2.4.9-1)
OSV
CVE-2021-32791: mod_auth_openidc is an authentication/authorization module for the Apache 2
osv·2021-07-26·CVSS 5.9
CVE-2021-32791 [MEDIUM] CVE-2021-32791: mod_auth_openidc is an authentication/authorization module for the Apache 2
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.
No detection rules found.
No public exploits indexed.
https://github.com/zmartzone/mod_auth_openidc/commit/375407c16c61a70b56fdbe13b0d2c8f11398e92chttps://github.com/zmartzone/mod_auth_openidc/releases/tag/v2.4.9https://github.com/zmartzone/mod_auth_openidc/security/advisories/GHSA-px3c-6x7j-3r9rhttps://lists.debian.org/debian-lts-announce/2023/04/msg00034.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FZVF6BSJLRQZ7PFFR4X5JSU6KUJYNOCU/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QXAWKPT5LXZSUTFSJ6IWSZC7RMYYQXQD/https://www.oracle.com/security-alerts/cpuapr2022.htmlhttps://github.com/zmartzone/mod_auth_openidc/commit/375407c16c61a70b56fdbe13b0d2c8f11398e92chttps://github.com/zmartzone/mod_auth_openidc/releases/tag/v2.4.9https://github.com/zmartzone/mod_auth_openidc/security/advisories/GHSA-px3c-6x7j-3r9rhttps://lists.debian.org/debian-lts-announce/2023/04/msg00034.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FZVF6BSJLRQZ7PFFR4X5JSU6KUJYNOCU/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QXAWKPT5LXZSUTFSJ6IWSZC7RMYYQXQD/https://www.oracle.com/security-alerts/cpuapr2022.html
2021-07-26
Published