{"id":"CVE-2026-4633","aliases":["GHSA-rhgq-f8x5-j2jc"],"title":"Keycloak's identity-first login flow exposes user information","summary":"Keycloak's identity-first login flow exposes user information","severity":"low","cvss":3.7,"cwe":["CWE-209"],"vendor":"keycloak","product":"org.keycloak:keycloak-services","ecosystem":"maven","affected":["org.keycloak:keycloak-services >= 26.5.0, < 26.6.1","org.keycloak:keycloak-services < 26.4.12"],"patched":["org.keycloak:keycloak-services 26.6.1","org.keycloak:keycloak-services 26.4.12"],"published":"2026-03-23","updated":"2026-10-23","sourceUpdated":"2026-10-23T00:32:50Z","source":"GHSA","sourceUrl":"https://github.com/advisories/GHSA-rhgq-f8x5-j2jc","references":[{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-4633"},{"url":"https://access.redhat.com/security/cve/CVE-2026-4633"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2450247"},{"url":"https://github.com/keycloak/keycloak/issues/47619"},{"url":"https://github.com/keycloak/keycloak/commit/b137016cc6dcfd9f59b2aa2e6d73af8b0ebf7c6e"},{"url":"https://github.com/keycloak/keycloak/commit/b4558a874fa79341404ae4d2d8f240f22bfed340"},{"url":"https://github.com/keycloak/keycloak/pull/47635"},{"url":"https://access.redhat.com/errata/RHSA-2026:19596"},{"url":"https://github.com/advisories/GHSA-rhgq-f8x5-j2jc"}],"tags":["ghsa","maven","cve.org"],"epss":0.00379,"epssPercentile":0.30704,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-03-23T15:07:15.419255Z"},"ingestedAt":"2026-10-22T22:00:50.444Z","slug":"CVE-2026-4633","body":"## Overview\n\nA 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.\n\n## Affected packages\n\n- `org.keycloak:keycloak-services >= 26.5.0, < 26.6.1`\n- `org.keycloak:keycloak-services < 26.4.12`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `org.keycloak:keycloak-services 26.6.1`\n- `org.keycloak:keycloak-services 26.4.12`","depth":"sunlit","depthScore":20,"depthScoreParts":{"impact":20.4,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}