W32/Rbot-AJL

Please follow the instructions for removing worms.

You will also need to edit the following registry entries, if they are present. Please read the warning about editing the registry.

At the taskbar, click Start|Run. Type 'Regedit' and press Return. The registry editor opens.

Before you edit the registry, you should make a backup. On the 'Registry' menu, click 'Export Registry File'. In the 'Export range' panel, click 'All', then save your registry as Backup.

Locate the HKEY_LOCAL_MACHINE entries:

HKLM\Software\Microsoft\Windows\CurrentVersion\Run

HKLM\Software\Microsoft\Windows\CurrentVersion\RunServices

and remove any reference to any file you deleted.

Close the registry editor.

Check the following items

• To renable DCOM you can edit the registry, but it's better to use Dcomcnfg.exe. See Microsoft article 825750 for details.
• The HKLM\SYSTEM\CurrentControlSet\Control\Lsa\restrictanonymous = "1" setting does not allow enumeration of SAM accounts and names. The default is "0". It can be changed in Local Security Policy. See Microsoft article 246261 for details.

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

W32/Rbot-AJL 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) and Veritas (CAN-2004-1172) and by copying itself to network shares protected by weak passwords.

W32/Rbot-AJL 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-AJL copies itself to the Windows system folder as winPE.exe.

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

HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
ms ownage
winPE.exe

HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\RunServices
ms ownage
winPE.exe

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

HKLM\SYSTEM\CurrentControlSet\Services\SharedAccess
Start
4

HKLM\SYSTEM\CurrentControlSet\Services\wuauserv
Start
4

Registry entries are set as follows:

HKCU\Software\Microsoft\OLE
ms ownage
winPE.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

The following patches for the operating system vulnerabilities exploited by W32/Rbot-AJL can be obtained from the Microsoft website:

MS02-039
MS03-049
MS04-011
MS04-012