What is it?
xxx.exe is a copy of the executable code that contains the w32.bugbear.m worm

What does it do?
the xxx.exe file has been reported to be copied into the startup folder of the infected system so that the worm is activated each time the computer is booted. The w32.bugbear.m worm itself is a mass-mailing worm that sends itself to email addresses it gathers from certain files on the system, using its own SMTP engine.

More information and removal instructions
@symantec