Backdoor.Snifula.D
Backdoor.Snifula.D is Symantec’s definition for a malware that is a variant of Snifula family of Trojan. This particular version can allow a remote attacker to gain control of the infected computer through backdoor. The Trojan frequently communicates to a remote server to download other malware that it can drop and execute on victim’s machine.
Damage Level: Medium
Systems Affected: Windows 9x, 2000, XP, Windows Vista
Characteristics
When executed, Backdoor.Snifula.D will directly hit Windows registry. It will include a ‘NoProtectedModeBanner’ to it in order to disable warning messages that Windows prompts each time an illegal activity occurs on the system. The same actions will carry out by the Trojan that will reduce the security settings on Internet Explorer. With this action, user may be prone to any virus attack while browsing the web.
Unlike most Trojan, Backdoor.Snifula.D does not create a registry entry to run itself on Windows start-up. Instead, this threat will inject harmful code into valid processes including explorer.exe, iexplore.exe, firefox.exe, chrome.exe, opera.exe, and safari.exe. Trojan will load if user runs any of these programs.
Then, the Trojan tries to contact a command and control (C&C) server through HTTP request on the same port 80, the same way users can connect to the Internet. During analysis, it was discovered that most of C&C servers that provides remote command for this threat are originating from .TW domains.
Lastly, Backdoor.Snifula.D attempts to gather cookie data from the infected computer. It is also interested in collecting Internet certificates and stores them under UserProfile folder.
[cf]regis[/cf] [cf]files[/cf]How to Remove Backdoor.Snifula.D
1. Temporarily Disable System Restore (Windows Me/XP).
2. To identify even the most recent variant of Backdoor.Snifula.D, open your antivirus application and update the virus definitions.
3. Start Windows in Safe Mode with Networking.
- From a power-off state, turn on the computer and press F8 repeatedly.
- Your computer will display Windows Advanced Boot Options menu. Select Safe Mode with Networking.
- System will boot Windows loading only necessary drivers and system files.
4. Open your antivirus program and run a full system scan. After the scan, delete all infected items. If unable to delete, better place them in quarantine. Once the scan is complete please proceed with the next step.
Scan with Norton Power Eraser:
Free tool from Symantec called Norton Power Eraser provides deep scanning technology to detect and remote threats like Backdoor.Snifula.D. NPE targets and eliminate threats that regular virus scan fails to identify. Download NPE here.
Important! Because of Norton Power Eraser’s aggressive method, it can select even legitimate files as suspicious. Please use this tool very carefully.
Alternative Removal Method for Backdoor.Snifula.D
Option 1 : Use Windows System Restore to return Windows to previous state
If Backdoor.Snifula.D enters the computer, there is a big chance that Windows files, registry entries and other essential components are also infected. System Restore can reinstate clean system files by restoring the configuration to an earlier date. The method also replaces compromised files with a clean version. If you have a saved restore point before Backdoor.Snifula.D infiltrates the PC, we highly encourage you to execute this procedure if none of the above works. You may proceed with Windows System Restore, click here to see the full procedure.
Option 2 : Backdoor.Snifula.D manual uninstall guide
IMPORTANT! Manual removal of Backdoor.Snifula.D requires technical skills. Deleting system files and registry entries by mistake may result to total disability of Windows system. We advise you to perform a backup of registry before proceeding with this guide.
1. Kill any running process that belongs to Backdoor.Snifula.D.
- Press Ctrl+Alt+Del on your keyboard.
- When Windows Task Manager appears, look for Backdoor.Snifula.D files (refer to Technical Reference) and click End Process.
2. Delete all registry entries that belong to this malware.
- Press [Windows Key]+R on your keyboard.
- In the 'Open' dialog box, type regedit and press Enter. This will open registry editor.
- Find and delete registry entries as mentioned in Technical Reference section below.
- Close registry editor. Changes made will be save automatically.
3. Scan the computer with antivirus program.
- Connect to Internet and open your antivirus software. Please update to obtain the latest database and necessary files.
- Restart the computer in Safe Mode.
- Just before Windows logo begins to load press F8 on your keyboard.
- On Windows Advanced Boot Options, select Safe Mode and press Enter.
4. Delete all files dropped by Backdoor.Snifula.D.
- While still in Safe Mode, search and delete malicious files. Please refer to 'Technical Reference'. Make sure that you execute 'End Task' first before deleting the file. Otherwise, the system will not let you perform this action.