BackDoor.Bolg

Virus type: Malicious spammer program

Affected OS: Win NT-based

File size: 25 600 bytes

Packed by: -

Technical description

Can be installed by various malicious downloaders and installers.

When launched injects its code in the alternative data stream (ADS) into %systemroot%\system32\svchost.exe.

In order to be launched at Windows start-up it registers the copy of %systemroot%\system32\svchost.exe as a service:

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\FCI\
ImagePath = %systemroot%\system32\svchost.exe:ext.exe

The displayed service name is FCI.

Adds the infected %systemroot%\system32\svchost.exe to the list of trusted applications of the Windows firewall .

Connects to a remote server and initiates spamming.

System restore information

1. Disconnect an infected machine from the local area network and/or the Internet. Disable the System Restore service.
2. Use an uninfected machine to download the Dr.Web CureIt!utility and place it on a removable media.
3. Boot Windows in the safe mode (F8 at start-up) and scan the infected computer using Dr.Web CureIt!. Apply “Cure” to all infected objects.

Curing recommendations

If the operating system (OS) can be loaded (either normally or in safe mode), download Dr.Web Security Space and run a full scan of your computer and removable media you use. More about Dr.Web Security Space.
If you cannot boot the OS, change the BIOS settings to boot your system from a CD or USB drive. Download the image of the emergency system repair disk Dr.Web® LiveDisk , mount it on a USB drive or burn it to a CD/DVD. After booting up with this media, run a full scan and cure all the detected threats.

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Use Dr.Web Anti-virus for macOS to run a full scan of your Mac.

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After booting up, run a full scan of all disk partitions with Dr.Web Anti-virus for Linux.

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If the mobile device is operating normally, download and install Dr.Web for Android. Run a full system scan and follow recommendations to neutralize the detected threats.
If the mobile device has been locked by Android.Locker ransomware (the message on the screen tells you that you have broken some law or demands a set ransom amount; or you will see some other announcement that prevents you from using the handheld normally), do the following:
- Load your smartphone or tablet in the safe mode (depending on the operating system version and specifications of the particular mobile device involved, this procedure can be performed in various ways; seek clarification from the user guide that was shipped with the device, or contact its manufacturer);
- Once you have activated safe mode, install the Dr.Web for Android onto the infected handheld and run a full scan of the system; follow the steps recommended for neutralizing the threats that have been detected;
- Switch off your device and turn it on as normal.

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Curing recommendations

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