🛡️ CVE-2026-18206 — build-of-keycloak

🟢 CVSS 3.7 — Low ✅ No Known Exploit CWE-20 NVD
3.7
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

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.

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is high, an attacker needs no privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality none, integrity low, availability none.

Weakness class

CVE-2026-18206 is classified as CWE-20: Improper Input Validation. The application accepts input without checking that it has the expected form, so malformed values reach code that assumes they are well formed.

Affected software

CVE-2026-18206 is recorded against 1 package.

  • build-of-keycloak

Timeline and source

Published on 31 July 2026 and last revised on 7 August 2026. No public exploit is currently recorded for this entry. Record sourced from NVD.

References

access.redhat.com
bugzilla.redhat.com

Details

Severity LOW
CVSS Score 3.7
CVSS Vector CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
CWE CWE-20
Public Exploit ✅ No
Source NVD
Published 2026-07-31
Updated 2026-08-11
Modified 2026-08-07
Fix URL N/A

Affected Packages

Software From version Fixed in
build-of-keycloak — —

Similar Threats

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