What is CVE-2026-18209?

CVE-2026-18209 is a low-severity vulnerability in Red Hat Build Of Keycloak, classified under CWE-1288. CVSS score: 3.4/10. Published 2026-07-31.

How severe is CVE-2026-18209?

Low severity. CVSS v3 base score is 3.4 out of 10.

Vulnerability in Red Hat Build Of Keycloak

CVE-2026-18209

A flaw was found in the keycloak-services component of Keycloak, which handles OpenID Connect (OIDC) authentication flows. The issue occurs because the security check designed to prevent HTTP parameter pollution only inspects the query por…

CVSS v3 metric

CVSS v3 base score 3.4 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:L/A:N.

Affected products

Red Hat Build Of Keycloak
Red Hat Data Grid 8
Red Hat Jboss Enterprise Application Platform Expansion Pack
Red Hat Single Sign-on 7

Weakness classification (CWE)

CWE-1288

References

secalert@redhat.com (x_refsource_REDHAT, vdb-entry)
secalert@redhat.com (x_refsource_REDHAT, issue-tracking)

Frequently asked questions

What is CVE-2026-18209?: CVE-2026-18209 is a low-severity vulnerability in Red Hat Build Of Keycloak, classified under CWE-1288. CVSS score: 3.4/10. Published 2026-07-31.
How severe is CVE-2026-18209?: Low severity. CVSS v3 base score is 3.4 out of 10.