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Vulnerability record · CVE-2026-4633 · published 23 March 2026

CVE-2026-4633: Redhat build of keycloak error message information leak vulnerability

Redhat · Build Of Keycloak

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.

3.7 CVSS 3.1 Low EPSS 0.37% · top 71.6% CWE-209 · Error message information leak
3.7CVSS 3.1 base score
0.37%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References, 1 tagged exploit
17 Jun 2026Last modified by NVD

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.

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://access.redhat.com/security/cve/CVE-2026-4633 Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2450247 ExploitIssue TrackingVendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-4633), CISA KEV, FIRST EPSS (scores of 2026-10-10). This page is refreshed as NVD updates the record.