{"id":"CVE-2026-18215","title":"Keycloak provides a way to let users log in using Microsoft accounts while restricting access to a specific organization (tenant)","summary":"Keycloak provides a way to let users log in using Microsoft accounts while restricting access to a specific organization (tenant). A flaw was discovered where this restriction is ignored when using the token exchange feature. This means …","severity":"medium","cvss":6.8,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N","cwe":["CWE-287"],"vendor":"redhat","product":"build_of_keycloak","affected":["build_of_keycloak"],"patched":["build_of_keycloak 26.6.7"],"published":"2026-07-31","updated":"2026-09-16","sourceUpdated":"2026-09-16T19:17:09.193","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-18215","references":[{"url":"https://access.redhat.com/errata/RHSA-2026:68277","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:68278","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/security/cve/CVE-2026-18215","label":"secalert@redhat.com"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2508309","label":"secalert@redhat.com"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-18215.json"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-18215"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-18215"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"epss":0.00226,"epssPercentile":0.13525,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-07-31T11:00:33.369953Z"},"ingestedAt":"2026-08-08T14:22:57.508Z","slug":"CVE-2026-18215","body":"## Overview\n\nKeycloak provides a way to let users log in using Microsoft accounts while restricting access to a specific organization (tenant). A flaw was discovered where this restriction is ignored when using the token exchange feature. This means an attacker with a valid Microsoft token from a completely different organization could gain access to the Keycloak realm, potentially accessing sensitive data or performing unauthorized actions.\n\n## Affected\n\n- `build_of_keycloak`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **RHSA-2026:68278** · Red Hat · fixed in: Red Hat build of Keycloak 26.6.7 · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:68278)\n- **RHSA-2026:68277** · Red Hat · fixed in: Red Hat build of Keycloak 26.6 · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:68277)","depth":"sunlit","depthScore":37,"depthScoreParts":{"impact":37.4,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}