You can view the active sessions in Salesforce and kill suspicious sessions if required. Navigate to Setup -> Security Controls -> Session Management. Select one or more sessions and click on Remove to end the suspicious sessions. Do not forget to freeze the user account (Setup -> Manage Users – Users) or reset their password if you suspect a compromise in the user account
![](https://amazon.asagarwal.com/images/2019_09_22_salesforce_session_management.png)