CVE-2023-6544: keycloak Permissive Regular Expression
Vulnerability summary
CVE-2023-6544 is a medium (CVSS 5.4) Permissive Regular Expression vulnerability in keycloak. EPSS estimates a 1.07% chance of exploitation in the next 30 days, higher than 64.4% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 3 · Related 3Timeline
- 25-04-2024PublishedVulnerability first disclosed.
- 11-11-2025Last modifiedVulnerability information updated.
Description
A flaw was found in the Keycloak package. This issue occurs due to a permissive regular expression hardcoded for filtering which allows hosts to register a dynamic client. A malicious user with enough information about the environment could jeopardize an environment with this specific Dynamic Client Registration and TrustedDomain configuration previously unauthorized.
CVSS metrics
5 scores · 5 sources · 1 version- OSV · WolfiEcosystem advisory · calculated5.4MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
- OSV · ChainguardEcosystem advisory · calculated5.4MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
- OSV · MavenEcosystem advisory · calculated5.4MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
- NVDNIST5.4MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
EPSS trend
Probability
1.07%
Chance of exploitation in the next 30 days
Percentile
64%
Versus all other CVEs
30-day change
0.00 pp
From 1.07% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Chainguard1 product
- keycloak< 24.0.3-r0
Org.keycloak1 product
- keycloak-services< 22.0.10 | ≥ 23.0.0, < 24.0.3
Wolfi1 product
- keycloak< 24.0.3-r0
3 vendors · 3 products
