W32/Tirbot
Analysis
- Copies itself to the System folder as MSDTCs.exe.
Registry Modification
- Adds the following registry entry to automatically execute itself during startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
IECheck = "undefinedSystemundefined\MSDTCs.exe"
Other Behavior
- Connects to the one of the following Internet Relay Chat (IRC) servers:
- b0t1n.mi{REMOVED}
- mast4.sy{REMOVED}
- r3v3ng3.a{REMOVED}
- squ4r3s.sy{REMOVED}
It joins the channel #r1sUn10n, then listens for commands that allow the remote attacker to perform any of the following actions:
- Remove itself from the system
- Update itself
- Get bot information
- Get process list
- Download files
- Upload files
- Peform Distributed Denial of Service (DDoS) attacks
- Check registry entries
- Delete registry entries
- Scan for antivirus monitors
- Spread itself through the network
- Get system information
Recommended Action
- FortiGate Systems
- Check the main screen using the web interface for your FortiGate unit to ensure that the latest AV/NIDS database has been downloaded and installed on your system - if required, enable the 'Allow Push Update' option.
FortiClient Systems
- Quarantine/delete files that are detected and replace infected files with clean backup copies.