low3.7
CVE-2026-4633
Keycloak's identity-first login flow exposes user information
Impact
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
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| maven | org.keycloak:keycloak-services | >= 26.5.0, < 26.6.1 | 26.6.1 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Redhat | Build Of Keycloak | All versions |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://access.redhat.com/errata/RHSA-2026:19596
- https://access.redhat.com/security/cve/CVE-2026-4633
- https://bugzilla.redhat.com/show_bug.cgi?id=2450247
- https://github.com/advisories/GHSA-rhgq-f8x5-j2jc
- https://nvd.nist.gov/vuln/detail/CVE-2026-4633
- https://github.com/keycloak/keycloak/issues/47619
- https://github.com/keycloak/keycloak/commit/b137016cc6dcfd9f59b2aa2e6d73af8b0ebf7c6e
- https://github.com/keycloak/keycloak/commit/b4558a874fa79341404ae4d2d8f240f22bfed340
- https://github.com/keycloak/keycloak/pull/47635