W32/Rbot-YR

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.

Each user has a registry area named HKEY_USERS\[code number indicating user]\. For each user locate the entry:

HKU\[code number]\Software\Microsoft\Windows\
CurrentVersion\Run\

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.
• Check your administrator passwords and review network security.

Sophos's anti-virus products include proactive detection technology, which can proactively protect against new threats without requiring an update.

W32/Rbot-YR is a worm which attempts to spread to remote network shares. It also contains backdoor functionality, allowing unauthorised remote access to the infected computer while running in the background as a service process.

W32/Rbot-YR spreads to network shares with weak passwords as a result of the Trojan element receiving the appropriate command from a remote user.

W32/Rbot-YR copies itself to the Windows System32 folder as tasksetup.exe and creates the following entries at these locations in the registry so as to run itself on system startup:

HKLM\Software\Microsoft\Windows\CurrentVersion\Run\
TASK SETUP
tasksetup.exe

HKLM\Software\Microsoft\Windows\CurrentVersion\RunServices\
TASK SETUP
tasksetup.exe

HKCU\Software\Microsoft\Windows\CurrentVersion\Run\
TASK SETUP
tasksetup.exe

W32/Rbot-YR may also set the following registry entries:

HKLM\SOFTWARE\Microsoft\Ole\
EnableDCOM
N

HKLM\SYSTEM\ControlSet001\Control\Lsa\
restrictanonymous
1

HKLM\SYSTEM\CurrentControlSet\Control\Lsa\
restrictanonymous
1

W32/Rbot-YR may try to delete network shares on the host computer. The worm may also attempt to steal keys for certain software installed on the machine.