CVE-2026-18215 — Keycloak-services: keycloak-services: microsoft external access-token exchange bypasses configured tenant
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 i…
Published: 2026-07-31 · CVSS: 6.8 · CVSS 3.1
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 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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7