In ARCHIBUS Web Central 21.3.3.815 (a version from 2014), the Web Application in /archibus/login.axvw assign a session token that could be already in use by another user. It was therefore possible to access the application through a user whose credentials were not known, without any attempt by the testers to modify the application logic. It is also possible to set the value of the session token, client-side, simply by making an unauthenticated GET Request to the Home Page and adding an arbitrary value to the JSESSIONID field. The application, following the login, does not assign a new token, continuing to keep the inserted one, as the identifier of the entire session. This is fixed in all recent versions, such as version 26. NOTE: This vulnerability only affects products that are no longer supported by the maintainer. Version 21.3 was officially de-supported by the end of 2020