CVE-2026-18215

high

Description

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.

References

Details

Source: Mitre, NVD

Published: 2026-07-31

Updated: 2026-09-16

Risk Information

CVSS v2

Base Score: 8.5

Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:N

Severity: High

CVSS v3

Base Score: 8.1

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

Severity: High

EPSS

EPSS: 0.00188