W32/Sdbot-OB 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/Sdbot-OB copies itself to the Windows system folder as DEZI.EXE and creates the following entries in the registry to run itself on system startup:
HKLM\Software\Microsoft\Windows\CurrentVersion\Run\
Configuration Loader = dezi.exe
HKLM\Software\Microsoft\Windows\CurrentVersion\RunServices\
Configuration Loader = dezi.exe
HKCU\Software\Microsoft\Windows\CurrentVersion\Run\
Configuration Loader = dezi.exe
W32/Sdbot-OB spreads to network shares with weak passwords as a result of the backdoor Trojan element receiving the appropriate command from a remote user.