Insufficient session revocation in OTRS lets old tokens stay valid

Previously issued authentication tokens are not immediately invalidated when an OTRS agent or customer user account is deactivated or its password is changed. As a result, an existing JWT may remain valid until its regular expiration time, which can be approximately 16 hours. An attacker who has previously obtained a valid authentication token can therefore continue to access OTRS with the privileges of the affected agent or customer user even after the corresponding account has been deactivated or the user's password has been changed. The vulnerability does not allow an attacker to obtain authentication tokens by itself. Exploitation requires possession of a previously issued and still valid token. The actual impact depends on the privileges associated with the compromised token. Customer user tokens are limited to the permissions of the affected customer account, while agent tokens may provide access to broader ticket, customer, or administrative functionality depending on the assigned permissions. This issue affects OTRS: * 7.0.X * 8.0.X * 2023.X * 2024.X * 2025.X * 2026.X before 2026.7.X