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CVE-2021-32786

Open Redirect in oidc_validate_redirect_url()

Published: Jul 22, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDUCWE-601
4.7MEDIUM
NVD MITRE
EPSS Score
2.4%
Top 18.0%
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, `oidc_validate_redirect_url()` does not parse URLs the same way as most browsers do. As a result, this function can be bypassed and leads to an Open Redirect vulnerability in the logout functionality. This bug has been fixed in version 2.4.9 by replacing any backslash of the URL to redirect with slashes to address a particular breaking change between the different specifications (RFC2396 / RFC3986 and WHATWG). As a workaround, this vulnerability can be mitigated by configuring `mod_auth_openidc` to only allow redirection whose destination matches a given regular expression.

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

zmartzone
oss-project
mod_auth_openidcOn-prem
Security Products / identity-access-mgmt
Сообщество свободного программного обеспечения
oss-projectaka fsf
Debian GNU/LinuxOn-premOS
Operating Systems / linux-distro
ZmartZone IAM
commercialaka zmartzone, mod_auth_openidc
Mod_auth_openidcMixed
Security Products / identity-access-mgmt
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

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/releases/tag/v2.4.9
github.com
https://github.com/zmartzone/mod_auth_openidc/security/advisories/GHSA-xm4c-5wm5-jqv7
github.com
https://github.com/zmartzone/mod_auth_openidc/commit/3a115484eb927bc6daa5737dd84f88ff4bbc5544
github.com
and 11 more references View all →

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