7.5

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. 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.

Data is provided by the National Vulnerability Database (NVD)
Openidc ≫ Mod Auth Openidc Version < 2.4.9
   Apache ≫ HTTP Server Version >= 2.0.0 <= 2.4.48
Netapp ≫ Cloud Backup Version-
Debian ≫ Debian Linux Version10.0
Zu dieser CVE wurde keine CISA KEV oder CERT.AT-Warnung gefunden.
EPSS Metriken
Type Source Score Percentile
EPSS FIRST.org 0.42% 0.615
CVSS Metriken
Source Base Score Exploit Score Impact Score Vector string
nvd@nist.gov 7.5 3.9 3.6
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvd@nist.gov 4.3 8.6 2.9
AV:N/AC:M/Au:N/C:N/I:N/A:P
security-advisories@github.com 5.3 3.9 1.4
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CWE-134 Use of Externally-Controlled Format String

The product uses a function that accepts a format string as an argument, but the format string originates from an external source.