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CVE-2021-39191

URL Redirection to Untrusted Site ('Open Redirect') in mod_auth_openidc

Published: Sep 3, 2021Updated: Nov 21, 2024 Sources: CVE List NVDCWE-601
4.7MEDIUM
NVD MITRE
EPSS Score
1.8%
Top 24.5%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

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 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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:RS:CC:NI:LA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:RUser Interaction
Required
Scope
S:CScope
Changed
Impact
C:NConfidentiality
None
I:LIntegrity
Low
A:NAvailability
None
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Weaknesses

CWE-601

Affected Products

openidc
oss-projectaka mod_auth_openidc, mod auth openidc, cjose
mod auth openidcLibrary
OSS Libraries / generic-library
fedoraproject
oss-project·USaka fedora project
fedoraOn-premOS
Operating Systems / linux-distro
debian
oss-project·GBaka debian gnu/linux
debian linuxOn-premOS
Operating Systems / linux-distro
zmartzone
oss-project
mod_auth_openidcOn-prem
Security Products / identity-access-mgmt

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Initial Access
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References

https://github.com/zmartzone/mod_auth_openidc/commit/03e6bfb446f4e3f27c003d30d6a433e5dd8e2b3d
github.com
https://github.com/zmartzone/mod_auth_openidc/issues/672
github.com
https://github.com/zmartzone/mod_auth_openidc/releases/tag/v2.4.9.4
github.com
and 4 more references View all →

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