6.1

CVE-2021-39191

Exploit

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 2.4.9.4, the 3rd-party init SSO functionality of mod_auth_openidc was reported to be vulnerable to an open redirect attack by supplying a crafted URL in the `target_link_uri` parameter. A patch in version 2.4.9.4 made it so that the `OIDCRedirectURLsAllowed` setting must be applied to the `target_link_uri` parameter. There are no known workarounds aside from upgrading to a patched version.

Data is provided by the National Vulnerability Database (NVD)
Openidc ≫ Mod Auth Openidc Version < 2.4.9.4
Fedoraproject ≫ Fedora Version35
Fedoraproject ≫ Fedora Version36
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% 0.616
CVSS Metriken
Source Base Score Exploit Score Impact Score Vector string
nvd@nist.gov 6.1 2.8 2.7
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
nvd@nist.gov 5.8 8.6 4.9
AV:N/AC:M/Au:N/C:P/I:P/A:N
security-advisories@github.com 4.7 2.8 1.4
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N
CWE-601 URL Redirection to Untrusted Site ('Open Redirect')

The web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect.