CVE-2026-4633

LOW3.7EPSS 0.02%

Keycloak's identity-first login flow exposes user information

Published: 3/23/2026Modified: 4/13/2026

Description

A flaw was found in Keycloak. A remote attacker can exploit differential error messages during the identity-first login flow when Organizations are enabled. This vulnerability allows an attacker to determine the existence of users, leading to information disclosure through user enumeration.

Affected packages (1)

Maven/org.keycloak:keycloak-services>= 26.5.0, < 26.6.0

CVSS scores

Source	Version	Severity	Vector
osv	CVSS 3.1	LOW3.7	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

References (7)

ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2026-4633
PATCHhttps://github.com/keycloak/keycloak
WEBhttps://access.redhat.com/security/cve/CVE-2026-4633
WEBhttps://bugzilla.redhat.com/show_bug.cgi?id=2450247
WEBhttps://github.com/keycloak/keycloak/commit/b137016cc6dcfd9f59b2aa2e6d73af8b0ebf7c6e
WEBhttps://github.com/keycloak/keycloak/commit/b4558a874fa79341404ae4d2d8f240f22bfed340
WEBhttps://github.com/keycloak/keycloak/issues/47619