Malware
jason
Jason is a graphic tool implemented to perform Microsoft exchange account brute-force in order to “harvest” the highest possible emails and accounts information.
jason is a Windows malware family operated by OilRig.
Background
Jason is a GUI utility built to brute-force Microsoft Exchange accounts so as to "harvest" as many emails and account details as possible. Shipped inside a ZIP archive, its interface is straightforward: the operator supplies the Microsoft Exchange address and its version. The tool offers a choice of three brute-force methods, EWS (Exchange Web Service), OAB (Offline Address Book), or both (All). Username and password lists can be loaded, and a thread count is specified to tune the attack.
Source: Malpedia (Fraunhofer FKIE).