Sophos

W32/Rbot-ATK

Aliases
  • Backdoor.Win32.Rbot.gen
  • W32/Sdbot.worm.gen.ac
Category
Type
What to do
Prevalence low high

Summary

 
How it spreads
  • Network shares
Affected operating systems Windows
Characteristics
  • Installs itself in the registry
Included in our products from December 2005 (4.00)
Protection available since 27 October 2005 08:03:28 (GMT)
Detected by All Sophos products

Action

More Information

W32/Rbot-ATK is a worm and IRC backdoor Trojan for the Windows platform.

W32/Rbot-ATK spreads to other network computers by exploiting common buffer overflow vulnerabilities, including: LSASS (MS04-011), RPC-DCOM (MS04-012), WKS (MS03-049) (CAN-2003-0812), MSSQL (MS02-039) (CAN-2002-0649), PNP (MS05-039) and ASN.1 (MS04-007) and by copying itself to network shares protected by weak passwords.

W32/Rbot-ATK 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.

When first run W32/Rbot-ATK copies itself to <System>\csrssv.exe and creates the file <Temp>\1.reg.

The following registry entries are created to run csrssv.exe on startup:

HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
Microsoft DLL Verifier
csrssv.exe

HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\RunServices
Microsoft DLL Verifier
csrssv.exe

W32/Rbot-ATK sets the following registry entries, disabling the automatic startup of other software:

HKLM\SYSTEM\CurrentControlSet\Services\wuauserv
Start
4

HKLM\SYSTEM\CurrentControlSet\Services\SharedAccess
Start
4

Registry entries are set as follows:

HKCU\Software\Microsoft\OLE
Microsoft DLL Verifier
csrssv.exe

HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings
MaxConnectionsPer1_0Server
50

HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings
MaxConnectionsPerServer
50

HKLM\SOFTWARE\Microsoft\Ole
EnableDCOM
N

HKLM\SYSTEM\CurrentControlSet\Control\Lsa
restrictanonymous
1

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