The equipment grants a JWT token for each connection in the timeline, but during an active valid session, a hijacking of the token can be done. This will allow an attacker with the token modify parameters of security, access or even steal the session without the legitimate and active session detecting it. The web server allows the attacker to reuse an old session JWT token while the legitimate session is active.
According to WASC, “Insufficient Session Expiration is when a web site permits an attacker to reuse old session credentials or session IDs for authorization.”