CVE-2026-4633

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.

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 LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:19596
https://access.redhat.com/security/cve/CVE-2026-4633	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2450247	Exploit Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

22 Oct 2026, 22:18

Type	Values Removed	Values Added
References		() https://access.redhat.com/errata/RHSA-2026:19596 -

Information

Published : 2026-03-23 11:16

Updated : 2026-10-22 22:18

NVD link : CVE-2026-4633

Mitre link : CVE-2026-4633

CVE.ORG link : CVE-2026-4633

JSON object : View

Products Affected

redhat

build_of_keycloak

CWE

CWE-209

Generation of Error Message Containing Sensitive Information

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