CVE-2026-18206

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.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-18206	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2508292	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:-:*:*:*

History

No history.

Information

Published : 2026-07-31 08:16

Updated : 2026-08-07 14:54

NVD link : CVE-2026-18206

Mitre link : CVE-2026-18206

CVE.ORG link : CVE-2026-18206

JSON object : View

Products Affected

redhat

build_of_keycloak

CWE

CWE-20

Improper Input Validation

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