CVE-2022-23527 | Open Redirect in oidc_validate_redirect_url()

mod_auth_openidc is an OpenID Certified™ authentication and authorization module for the Apache 2.x HTTP server. Versions prior to 2.4.12.2 are vulnerable to Open Redirect. When providing a logout parameter to the redirect URI, the existing code in oidc_validate_redirect_url() does not properly check for URLs that start with /\t, leading to an open redirect. This issue has been patched in version 2.4.12.2. Users unable to upgrade can mitigate the issue by configuring mod_auth_openidc to only allow redirection when the destination matches a given regular expression with OIDCRedirectURLsAllowed.

Published: 2022-12-14 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2022-23527 is rated Low Risk (38.3/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.90%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2022-23527

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.52% 0.90% +0.38%
2 2026-05-28 0.42% 0.52% +0.10%
3 2026-01-16 — 0.42% —

Full EPSS history (16 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2022-23527

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.7 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 1.4 [email protected]
6.1 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 2.7 [email protected]

Weakness enumeration for CVE-2022-23527

OS Trackers for CVE-2022-23527

vendor priority summary link
debian not yet assigned CVE-2022-23527 not yet assigned priority: Debian including 1 source packages (libapache2-mod-auth-openidc), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2022-23527
redhat medium — https://access.redhat.com/security/cve/CVE-2022-23527
suse medium CVE-2022-23527 severity moderate: SUSE including 9 source package names (apache2-mod_auth_openidc-2.3.8-150100.3.22.1, apache2-mod_auth_openidc-2.4.0-7.9.1, …), 21 product×package rows across 19 product lines (SUSE Liberty Linux 8, SUSE Liberty Linux 9, … (19 product lines)): Fixed 21. https://www.suse.com/security/cve/CVE-2022-23527/
ubuntu medium CVE-2022-23527 medium priority: Ubuntu including 1 source packages (libapache2-mod-auth-openidc), 13 status rows across 13 suites (bionic, focal, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 6, ignored 3, needed 3, released 1. https://ubuntu.com/security/CVE-2022-23527

Affected software / configurations for CVE-2022-23527

Vendor Product Version Raw CPE
openidc mod_auth_openidc < 2.4.12.2 cpe:2.3:a:openidc:mod_auth_openidc:*:*:*:*:*:*:*:*
debian debian_linux 10.0 cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

References for CVE-2022-23527

cvelogic Threat Intelligence