W32/Rbot-AJ is a worm which attempts to spread to remote network shares. It also contains backdoor Trojan functionality, allowing unauthorised remote
access to the infected computer via IRC channels while running in the
background as a service process.
W32/Rbot-AJ spreads to network shares with weak passwords as a result of the backdoor Trojan element receiving the appropriate command from a remote user.
W32/Rbot-AJ copies itself to the Windows System32 folder as SYS.EXE and creates entries in the registry at the following locations to run itself on system startup:
HKLM\Software\Microsoft\Windows\CurrentVersion\Run\
Microsoft Update = sys.exe
HKLM\Software\Microsoft\Windows\CurrentVersion\RunServices\
Microsoft Update = sys.exe
HKCU\Software\Microsoft\Windows\CurrentVersion\Run\
Microsoft Update = sys.exe