Insufficient Session Expiration
A flaw was found in Keycloak in versions before 9.0.2. This flaw allows a malicious user that is currently logged in, to see the personal information of a previously logged out user in the account manager section.
CWE-613 - Insufficient Session Expiration
According to WASC, "Insufficient Session Expiration is when a web site permits an attacker to reuse old session credentials or session IDs for authorization."