Hello, an -shm sqlite file it is a shared-memory file. The shared-memory files is to provide a block of shared memory for use by multiple processes all accessing the same database in a specific mode. The shared-memory file, '''when''' exists, is located in the same directory as the database file (places.sqlite) and has the same name as the database file except with the 4 characters "-shm" appended (places.sqlite-shm) This kind of file only exist while firefox running(while it is open, active). If you close firefox the places.sqlite-shm not exist any more. Check it with your Hitman Pro. Probably nothing to worry about, it is a false alarm of your antivirus. :-) (btw, Hitman Pro said suspicious not malicious). :-) Again nothing to worry about. thank you