How to eliminate Backdoor.SDBot trojan from the operating system

Also Known As: Backdoor.SDBot virus
Type: Trojan
Damage level: Severe

What is Backdoor.SDBot?

Backdoor.SDBot is a malicious program and (as its name suggests) is a backdoor trojan. Typically, the main goal of trojans of this type is to give the attacker access to an infected computer (by opening a 'backdoor' by connecting to an IRC channel) or to send commands to it.

The program was first released in 2002, however, cyber criminals continually release new updates. This trojan mostly targets Windows users. Note that Backdoor.SDBot is capable of updating itself by checking for newer versions on the web. It can cause serious problems and should be removed immediately.

Backdoor.SDBot malware

More about Backdoor.SDBot

A trojan is software that is usually designed to operate silently. I.e., it is disguised as a supposedly legitimate process or software. People might not suspect that their computers are infected with trojans for some time.

There are, however, a number of symptoms that can help to detect the presence of Backdoor.SDBot: the operating system displays errors; it runs slowly; the system shuts down or restarts randomly; there are unknown processes running in the Task Manager or duplicate .exe (or other executables) files are created, or; unknown programs are running in the background. 

Backdoor.SDBot is designed to store files (executables) in system folders ("%System%") and the names of these vary depending on the trojan variant. Note, however, that the names are likely to be identical to genuine system files, which actually belong to the operating system. This trojan might be used to download and open/execute various harmful files.

Cyber criminals could use this technique to infect computers with other malicious software such as ransomware, keystroke loggers, cryptocurrency miners, and so on. Ransomware is software that is used to prevent victims from accessing their files by encryption. To regain access to their files, victims are encouraged to pay a ransom (purchase a decryption tool/key).

Typically, users who have computers infected with these programs experience data loss. If the system is infiltrated with a keystroke logger, it might be used to steal personal details such as banking credentials and passwords and logins of other accounts. Keystroke loggers record every key pressed on the keyboard.

Cyber criminals use these programs to steal information that might be used to generate revenue. Cryptocurrency miners use hardware (such as CPU, GPU) that is installed on victims' computers to solve mathematical problems, thereby mining cryptocurrency. Computers often become unusable or have reduced performance.

They also use more power, which leads to higher electricity bills. Trojans such as Backdoor.SDBot can also be used to infect the computers of other users. Furthermore, Backdoor.SDBot might be used to take screenshots (screen captures), thus allowing cyber criminals to steal personal information/details.

This backdoor trojan could be used to perform DoS (denial-of-service) attacks. These attacks are carried out to render machines or network resources unavailable to the intended users by sending multiple queries simultaneously - this eventually causes the target (e.g., the server) to crash, since it is unable to handle the volume of queries received.

Note also that Backdoor.SDBot can uninstall itself by eliminating all related registry entries. To prevent this situation, we recommend that you eliminate this trojan immediately.

Threat Summary:
Name Backdoor.SDBot virus
Threat Type Trojan, Password-stealing virus, Banking malware, Spyware
Detection Names (Bandicam. AegisLab (Trojan.Win32.Generic.4!c), Comodo (Malware@#3ukv4t94np0qz), ESET-NOD32 (Win32/Keygen.KL Potentially Unsafe), McAfee (RDN/Sdbot.worm!cc), Full List (VirusTotal)
Payload Backdoor trojan
Symptoms Trojans are designed to stealthily infiltrate the victim's computer and remain silent, and thus no particular symptoms are clearly visible on an infected machine.
Distribution methods Infected email attachments, malicious online advertisements, social engineering, software 'cracks', fake update tools.
Damage Stolen banking information, passwords, identity theft, victim's computer added to a botnet, installation of other threats.
Malware Removal (Windows)

To eliminate possible malware infections, scan your computer with legitimate antivirus software. Our security researchers recommend using Combo Cleaner.
▼ Download Combo Cleaner
To use full-featured product, you have to purchase a license for Combo Cleaner. 7 days free trial available. Combo Cleaner is owned and operated by Rcs Lt, the parent company of PCRisk.com read more.

Examples of trojans

Some examples of other programs categorized as trojans include Qakbot, Emotet, LokiBot, and Adwind. In most cases, people are unaware that their computers are infected with trojans. Cyber criminals use them to proliferate other malware, steal personal details, and cause damage in other ways.

Victims usually experience problems with finances/bank accounts, privacy, browsing safety, data loss, and so on. Therefore, take all measures to avoid having your computer infected with programs of this type.

How did Backdoor.SDBot infiltrate my computer?

Cyber criminals usually proliferate trojans and other malicious programs through spam campaigns, unofficial file or software download channels, fake software update tools, and software 'cracking' tools. Spam campaign proliferate computer infections by sending emails that contain malicious attachments (files).

These might be Microsoft Office documents, PDF or archive files (such as ZIP, RAR), executable files such as .exe, JavaScript files, etc. The main purpose of these campaigns is to trick recipients into downloading and opening the attached file. When opened, it triggers download and installation of a high-risk threat.

Untrustworthy, dubious software download sources such as freeware download websites, free file hosting sites, Peer-to-Peer networks (torrent clients, eMule, and so on) are used to disguise harmful software or files as legitimate. People who use these sources to download files or software risk to installation of computer infections.

Fake software update tools (updaters) cause damage when they download malware rather than updates, or they exploit bugs and flaws of outdated software. Some people use 'cracking' tools to bypass activation of paid programs/operating systems, however, they often download and install malicious programs instead.

How to avoid installation of malware?

To keep computers safe from ransomware, trojans, malware and so on, we recommend that you download, install, update software, and browse the Internet with care. Do not download files or software using dubious sources. Download from official and trustworthy websites only.

Update installed programs with implemented functions or tools that are designed by official software developers. The same applies to software activation. Use of 'cracks' and cracking tools is illegal and, furthermore, they are often the reason behind installation of malicious programs.

Attachments that are included in irrelevant emails should not be opened, especially if they are sent from unknown addresses. Prevent damage caused by malicious programs by regularly running scans with reputable (and updated) anti-spyware/anti-virus software.

If you believe that your computer is already infected, we recommend running a scan with Combo Cleaner Antivirus for Windows to automatically eliminate infiltrated malware.

Known names of files that can be used to disguise Backdoor.SDBot trojan (files are placed in the "%System%" folder):

Aim95.exe, CMagesta.exe, Cmd32.exe, Cnfgldr.exe, Explorer.exe, FB_PNU.EXE, IEXPL0RE.EXE, MSTasks.exe, MSsrvs32.exe, Mssql.exe, Regrun.exe, Svchosts.exe, Sys32.exe, Sys3f2.exe, Syscfg32.exe, Sysmon16.exe, YahooMsgr.exe, cthelp.exe, iexplore.exe, ipcl32.exe, quicktimeprom.exe, service.exe, sock32.exe, spooler.exe, svhost.exe, syswin32.exe, vcvw.exe, winupdate32.exe, xmconfig.exe

The Backdoor.SDBot trojan is designed to modify system options by adding the following rules/values:

  • "Configuration Loader" = "%System%\iexplore.exe"
  • "Configuration Loader" = "MSTasks.exe"
  • "Configuration Loader" = "aim95.exe"
  • "Configuration Loader" = "cmd32.exe"
  • "Configuration Loader"= "IEXPL0RE.EXE"
  • "Configuration Manager" = "Cnfgldr.exe"
  • "Fixnice" = "vcvw.exe"
  • "Internet Config" = "svchosts.exe"
  • "Internet Protocol Configuration Loader" = "ipcl32.exe
  • "MSSQL" = "Mssql.exe"
  • "MachineTest" = "CMagesta.exe"
  • "Microsoft Synchronization Manager" = "svhost.exe"
  • "Microsoft Synchronization Manager" = "winupdate32.exe"
  • "Microsoft Video Capture Controls" = "MSsrvs32.exe"
  • "Quick Time file manager" = "quicktimeprom.exe"
  • "Registry Checker" = "%System%\Regrun.exe"
  • "Sock32" = "sock32.exe"
  • "System Monitor" = "Sysmon16.exe"
  • "System33" = "%System%\FB_PNU.EXE"
  • "Windows Configuration" = "spooler.exe"
  • "Windows Explorer" = " Explorer.exe"
  • "Windows Services" = "service.exe"
  • "Yahoo Instant Messenger" = "Yahoo Instant Messenger"
  • "cthelp" = "cthelp.exe"
  • "stratas" = "xmconfig.exe"
  • "syswin32" = "syswin32.exe"

In addition, Backdoor.SDBot might modify the following Windows Registry entries:

  • HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
  • HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\
  • HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run\RunServices

Files that might be created by Backdoor.SDBot trojan:

  • %System%\SVKP.sys (Clean driver file that can be used for malicious purposes)
  • %System%\msdirectx.sys (This file is designed to provide rootkit functionality and anti-virus suites detect it as Hacktool.Rootkit)

Known IRC servers used by the Backdoor.SDBot trojan:

  • bmu.FL0W1NG.NET
  • bmu.h4x0rs.org
  • bmu.q8hell.org

The list of actions cyber criminals can perform using Backdoor.SDBot includes:

  • Completely uninstall the trojan by removing the certain registry entries
  • Download and execute files
  • Dynamically update the Trojan
  • Gather system/network information
  • Manage the IRC client on an infected machine
  • Manage the installation of the back door
  • Perform Denial of Service (DoS) attacks
  • Send the Trojan to other IRC channels with attempts to inject it into other machines

Example of a spam email used to distribute Backdoor.SDBot trojan:

SDBot malware-spreading spam email

Text presented within:

Subject: Certificate

Dear all,

Whatever you have suggested correction have been made please share your valuable suggestion before going to final print.

Thanks & Regards
*Kamal Kumar*
(Product Manager)

Instant automatic malware removal: Manual threat removal might be a lengthy and complicated process that requires advanced IT skills. Combo Cleaner is a professional automatic malware removal tool that is recommended to get rid of malware. Download it by clicking the button below:
▼ DOWNLOAD Combo Cleaner By downloading any software listed on this website you agree to our Privacy Policy and Terms of Use. To use full-featured product, you have to purchase a license for Combo Cleaner. 7 days free trial available. Combo Cleaner is owned and operated by Rcs Lt, the parent company of PCRisk.com read more.

Quick menu:

How to remove malware manually?

Manual malware removal is a complicated task - usually it is best to allow antivirus or anti-malware programs to do this automatically.

To remove this malware we recommend using Combo Cleaner Antivirus for Windows. If you wish to remove malware manually, the first step is to identify the name of the malware that you are trying to remove. Here is an example of a suspicious program running on a user's computer:

malicious process running on user's computer sample

If you checked the list of programs running on your computer, for example, using task manager, and identified a program that looks suspicious, you should continue with these steps:

manual malware removal step 1 Download a program called Autoruns. This program shows auto-start applications, Registry, and file system locations:

screenshot of autoruns application

manual malware removal step 2Restart your computer into Safe Mode:

Windows XP and Windows 7 users: Start your computer in Safe Mode. Click Start, click Shut Down, click Restart, click OK. During your computer start process, press the F8 key on your keyboard multiple times until you see the Windows Advanced Option menu, and then select Safe Mode with Networking from the list.

Safe Mode with Networking

Video showing how to start Windows 7 in "Safe Mode with Networking":

Windows 8 users: Start Windows 8 is Safe Mode with Networking - Go to Windows 8 Start Screen, type Advanced, in the search results select Settings. Click Advanced startup options, in the opened "General PC Settings" window, select Advanced startup. Click the "Restart now" button.

Your computer will now restart into the "Advanced Startup options menu". Click the "Troubleshoot" button, and then click the "Advanced options" button. In the advanced option screen, click "Startup settings". Click the "Restart" button. Your PC will restart into the Startup Settings screen. Press F5 to boot in Safe Mode with Networking.

Windows 8 Safe Mode with networking

Video showing how to start Windows 8 in "Safe Mode with Networking":

Windows 10 users: Click the Windows logo and select the Power icon. In the opened menu click "Restart" while holding "Shift" button on your keyboard. In the "choose an option" window click on the "Troubleshoot", next select "Advanced options". In the advanced options menu select "Startup Settings" and click on the "Restart" button.

In the following window you should click the "F5" button on your keyboard. This will restart your operating system in safe mode with networking.

windows 10 safe mode with networking

Video showing how to start Windows 10 in "Safe Mode with Networking":


manual malware removal step 3Extract the downloaded archive and run the Autoruns.exe file.

extract autoruns.zip and run autoruns.exe

manual malware removal step 4In the Autoruns application, click "Options" at the top and uncheck the "Hide Empty Locations" and "Hide Windows Entries" options. After this procedure, click the "Refresh" icon.

Click 'Options' at the top and uncheck 'Hide Empty Locations' and 'Hide Windows Entries' options

manual malware removal step 5Check the list provided by the Autoruns application and locate the malware filename that you want to eliminate.

You should write down its full path and name. Note that some malware hides process names under legitimate Windows process names. At this stage, it is very important to avoid removing system files. After you locate the suspicious program you wish to remove, right click your mouse over its name and choose "Delete".

locate the malware file you want to remove

After removing the malware through the Autoruns application (this ensures that the malware will not run automatically on the next system startup), you should search for the malware name on your computer. Be sure to enable hidden files and folders before proceeding. If you find the filename of the malware, be sure to remove it.

searching for malware file on your computer

Reboot your computer in normal mode. Following these steps should remove any malware from your computer. Note that manual threat removal requires advanced computer skills. If you do not have these skills, leave malware removal to antivirus and anti-malware programs.

These steps might not work with advanced malware infections. As always it is best to prevent infection than try to remove malware later. To keep your computer safe, install the latest operating system updates and use antivirus software.

To be sure your computer is free of malware infections, we recommend scanning it with Combo Cleaner Antivirus for Windows.

Frequently Asked Questions (FAQ)

My computer is infected with Backdoor.SDBot malware, should I format my storage device to get rid of it?

Formatting your storage device will effectively remove the Backdoor.SDBot malware, but it will also erase all data on the device. Thus, running a system scan using a reputable security tool like Combo Cleaner is advisable to try to detect and eliminate the malware.

What are the biggest issues that malware can cause?

Malware can cause a range of significant issues, including data loss or theft, financial losses through identity theft or fraud, and compromised system stability leading to crashes or slowdowns. Additionally, malware can cause privacy breaches and additional computer infections.

What is the purpose of Backdoor.SDBot?

It is likely that cybercriminals use this malware to inject additional payloads, allowing them to encrypt victims' files, steal sensitive information, access files, capture screenshots, or perform other malicious activities.

How did malware infiltrate my computer?

It is known that Backdoor.SDBot is delivered via emails containing malicious attachments. Also, it may be distributed using vulnerabilities in outdated software or operating systems, P2P networks, malicious advertisements, compromised or deceptive web pages, infected USB drives, and similar methods.

Will Combo Cleaner protect me from malware?

Combo Cleaner can detect and remove nearly all known malware. Sophisticated malware often conceals itself deep within the system. Thus, users whose computers are infected with this kind of malware are advised to run a full system scan to ensure removal.

▼ Show Discussion

About the author:

Tomas Meskauskas

Tomas Meskauskas - expert security researcher, professional malware analyst.

I am passionate about computer security and technology. I have an experience of over 10 years working in various companies related to computer technical issue solving and Internet security. I have been working as an author and editor for pcrisk.com since 2010. Follow me on Twitter and LinkedIn to stay informed about the latest online security threats. Contact Tomas Meskauskas.

PCrisk security portal is brought by a company RCS LT. Joined forces of security researchers help educate computer users about the latest online security threats. More information about the company RCS LT.

Our malware removal guides are free. However, if you want to support us you can send us a donation.

About PCrisk

PCrisk is a cyber security portal, informing Internet users about the latest digital threats. Our content is provided by security experts and professional malware researchers. Read more about us.

Malware activity

Global malware activity level today:

Medium threat activity

Increased attack rate of infections detected within the last 24 hours.

QR Code
Backdoor.SDBot virus QR code
Scan this QR code to have an easy access removal guide of Backdoor.SDBot virus on your mobile device.
We Recommend:

Get rid of Windows malware infections today:

Download Combo Cleaner

Platform: Windows

Editors' Rating for Combo Cleaner:
Editors ratingOutstanding!

[Back to Top]

To use full-featured product, you have to purchase a license for Combo Cleaner. 7 days free trial available. Combo Cleaner is owned and operated by Rcs Lt, the parent company of PCRisk.com read more.