Answer in brief
CVE-2026-18206 records a Low severity (CVSS 3.7) vulnerability in Keycloak-services: keycloak-services: client policy source-host wildcard domain matching bypass. The current sources do not mark it as known exploited. The current feed maps Red Hat/keycloak-services (generic), Red Hat/rhbk-keycloak-rhel9/rhbk-keycloak-rhel9 (generic), Red Hat/rhbk-openshift-rhel9/rhbk-openshift-rhel9 (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 3.7. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Red Hat/keycloak-services (generic), Red Hat/rhbk-keycloak-rhel9/rhbk-keycloak-rhel9 (generic), Red Hat/rhbk-openshift-rhel9/rhbk-openshift-rhel9 (generic). Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:-:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Red Hat/keycloak-servicesgeneric | * | Not reported |
| Red Hat/rhbk-keycloak-rhel9/rhbk-keycloak-rhel9generic | * | Not reported |
| Red Hat/rhbk-openshift-rhel9/rhbk-openshift-rhel9generic | * | Not reported |
Published upstream
Jul 31, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 31, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 3, 2026
A flaw was found in the keycloak-services component of Keycloak, which provides identity and access management services. The issue occurs when a realm administrator uses a wildcard domain (like *.example.com) to restrict which hosts can register or update clients. Due to improper validation, the system accepts any hostname that ends with the specified domain suffix, even if it is not a legitimate subdomain. An attacker who can control the reverse DNS of their connection can bypass these host-based restrictions, potentially allowing unauthorized client modifications.
Quoted source text, attributed separately from HOL analysis.