W32/Rbot-GCD is a worm with IRC backdoor functionality for the Windows platform.
W32/Rbot-GCD runs continuously in the background, providing a backdoor server which allows a remote intruder to gain access and control over the computer via IRC channels.
W32/Rbot-GCD spreads to other network computers by:
- exploiting common buffer overflow vulnerabilities, including: LSASS (MS04-011), RPC-DCOM (MS04-012), ASN.1 (MS04-007) and RealVNC (CVE-2006-2369)
- networks protected by weak passwords
When first run W32/Rbot-GCD copies itself to <System>\WinSecUp.exe.
The following registry entries are created to run svcchost.exe on startup:
HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\RunServices
Windows Secure Update
WinSecUp.exe
HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
Windows Secure Update
WinSecUp.exe
Registry entries are set as follows:
HKLM\CurrentControlSet\Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\List
<System>\WinSecUp.exe
<System>\WinSecUp.exe:*:Enabled:Windows Secure Update
HKCU\Software\Microsoft\OLE
Windows Secure Update
WinSecUp.exe
HKLM\SOFTWARE\Microsoft\Ole
EnableDCOM
N
HKLM\SYSTEM\CurrentControlSet\Control\Lsa
restrictanonymous
1
Registry changes may also be made under:
HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\
HKLM\SYSTEM\CurrentControlSet\Services\lanmanserver\parameters\
HKLM\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\
Protocols\PCT1.0\Server\
HKLM\SYSTEM\CurrentControlSet\Services\NetBT\Parameters\
HKLM\SYSTEM\CurrentControlSet\Services\SharedAccess\
HKLM\SYSTEM\CurrentControlSet\Services\wuauserv\
HKLM\SYSTEM\CurrentControlSet\Services\wscsvc\
W32/Rbot-GCD includes functionality to:
- perform port scanning
- act as a SOCKS4 proxy server
- terminates security and anti-virus related processes
- perform DDoS attacks
- download code from the internet
W32/Rbot-GCD also creates the file C:\a.bat. This file can be safely removed.