Security researchers at Dr.Web have reported a new Trojan, dubbed BackDoor.TeamViewer.49. According to the security firm, the threat is designed to install TeamViewer on targeted systems. Why is BackDoor.TeamViewer.49 doing that? To transmit web traffic to specific servers through using the host as a proxy server. The Trojan was discovered and analyzed just recently, and its distribution process is quite complex and multi-stage.
Threat Summary
| Name | BackDoor.TeamViewer.49 |
| Type | Backdoor Trojan |
| Short Description | The Trojan is used to relay Web traffic and hide the cyber criminals’ real IP address. |
| Symptoms | The victim installs a malicious Flash update package. |
| Distribution Method | Via a Trojan dropper and a malicious Flash update package. |
| Detection Tool | See If Your System Has Been Affected by BackDoor.TeamViewer.49 Download Malware Removal Tool |
| User Experience | Join Our Forum to Discuss BackDoor.TeamViewer.49. |
Technical Specifications of BackDoor.TeamViewer.49
Dr.Web reports that the Trojan is spread with the help of a Trojan dropper – Trojan.MulDrop6.39120. Softpedia says that the Trojan’s initial infection takes place via a corrupted Adobe Flash update package. In fact, Trojan.MulDrop6.39120 is spread online bundled with the Flash package. Once the potential victim installs the Flash update, the Trojan dropper is installed along with the TeamViewer app.
Contrary to what you may think TeamViewer is dropped for – taking over the compromised computer, obtaining sensitive information – it’s used for something else.
Cyber criminals replace TeamViewer’s avicap32.dll with a malicious version containing BackDoor.TeamViewer.49.
The Trojan’s main payload is incorporated into the avicap32.dll library. Trojan.MulDrop6.39120 runs TeamViewer that automatically loads the library to the computer’s memory. All lines, imports, and functions of TeamViewer’s process are actively implemented by this malicious library. The most critical parts of the Trojan’s code are encrypted with base64 and RC4.
Once TeamViewer is set and running, BackDoor.TeamViewer.49 connects to a command & control server using an encrypted channel, and awaits instructions. According to Dr.Web’s research, the analyzed versions mainly operate as a Web proxy, relaying traffic it receives from the command server to the Internet. This is how cyber criminals mask their real IP address.
Dr.Web also reports that the Trojan can execute the following commands received over HTTPS:
- disconnect—terminate the connection;
- idle—maintain the connection;
- updips—update the auth_ip list with the one specified in the command received;
- connect—connect to the specified host server. The command must consist of the following parameters:
- ip—host server’s IP address;
- auth_swith—use authorization. If the value is set to “1”, the Trojan receives the auth_login and auth_pass parameters. If the value is “0”, the Trojan gets the auth_ip parameter. Otherwise, the connection will not be established;
- auth_ip—IP authentication;
- auth_login—login;
- auth_pass—password.
How Can Users Protect Their PCs from BackDoor.TeamViewer.49?
As with other Trojans, the most secure way to prevent an infection is via having an active anti-malware protection on the system. If you have been affected, refer to the removal steps below to try and remove the Trojan completely.
Milena Dimitrova
An inspired writer and content manager who has been with SensorsTechForum since the beginning. Focused on user privacy and malware development, she strongly believes in a world where cybersecurity plays a central role. If common sense makes no sense, she will be there to take notes. Those notes may later turn into articles! Follow Milena @Milenyim
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Milena Dimitrova
An inspired writer and content manager who has been with SensorsTechForum since the beginning. Focused on user privacy and malware development, she strongly believes in a world where cybersecurity plays a central role. If common sense makes no sense, she will be there to take notes. Those notes may later turn into articles! Follow Milena @Milenyim
Follow Me:
Milena Dimitrova
An inspired writer and content manager who has been with SensorsTechForum since the beginning. Focused on user privacy and malware development, she strongly believes in a world where cybersecurity plays a central role. If common sense makes no sense, she will be there to take notes. Those notes may later turn into articles! Follow Milena @Milenyim
Follow Me:
Preparation before removing BackDoor.TeamViewer.49.
Before starting the actual removal process, we recommend that you do the following preparation steps.
- Make sure you have these instructions always open and in front of your eyes.
- Do a backup of all of your files, even if they could be damaged. You should back up your data with a cloud backup solution and insure your files against any type of loss, even from the most severe threats.
- Be patient as this could take a while.
Step 1: Boot Your PC In Safe Mode to isolate and remove BackDoor.TeamViewer.49
Step 2: Clean any registries, created by BackDoor.TeamViewer.49 on your computer.
The usually targeted registries of Windows machines are the following:
- HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
- HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunOnce
- HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce
You can access them by opening the Windows registry editor and deleting any values, created by BackDoor.TeamViewer.49 there. This can happen by following the steps underneath:
Tip: To find a virus-created value, you can right-click on it and click “Modify” to see which file it is set to run. If this is the virus file location, remove the value.Step 3: Find files created by BackDoor.TeamViewer.49
For Windows 8, 8.1 and 10.
For Windows XP, Vista, and 7.For Newer Windows Operating Systems
1: On your keyboard press + R and write explorer.exe in the Run text box and then click on the Ok button.
2: Click on your PC from the quick access bar. This is usually an icon with a monitor and its name is either “My Computer”, “My PC” or “This PC” or whatever you have named it.
3: Navigate to the search box in the top-right of your PC’s screen and type “fileextension:” and after which type the file extension. If you are looking for malicious executables, an example may be “fileextension:exe”. After doing that, leave a space and type the file name you believe the malware has created. Here is how it may appear if your file has been found:
N.B. We recommend to wait for the green loading bar in the navination box to fill up in case the PC is looking for the file and hasn’t found it yet.
For Older Windows Operating Systems
In older Windows OS’s the conventional approach should be the effective one:
1: Click on the Start Menu icon (usually on your bottom-left) and then choose the Search preference.
2: After the search window appears, choose More Advanced Options from the search assistant box. Another way is by clicking on All Files and Folders.
3: After that type the name of the file you are looking for and click on the Search button. This might take some time after which results will appear. If you have found the malicious file, you may copy or open its location by right-clicking on it.
Now you should be able to discover any file on Windows as long as it is on your hard drive and is not concealed via special software.
Before starting “Step 4”, please boot back into Normal mode, in case you are currently in Safe Mode.
This will enable you to install and use SpyHunter 5 successfully.
Step 4: Scan for BackDoor.TeamViewer.49 with SpyHunter Anti-Malware Tool
Step 5 (Optional): Try to Restore Files Encrypted by BackDoor.TeamViewer.49.
Ransomware infections and BackDoor.TeamViewer.49 aim to encrypt your files using an encryption algorithm which may be very difficult to decrypt. This is why we have suggested a data recovery method that may help you go around direct decryption and try to restore your files. Bear in mind that this method may not be 100% effective but may also help you a little or a lot in different situations.
For more “how-to” file recovery methods and steps, you can visit our instructive article on “How to Restore Files Encrypted by Ransomware (Without Decrypter)“.
Milena Dimitrova
An inspired writer and content manager who has been with SensorsTechForum since the beginning. Focused on user privacy and malware development, she strongly believes in a world where cybersecurity plays a central role. If common sense makes no sense, she will be there to take notes. Those notes may later turn into articles! Follow Milena @Milenyim
Follow Me:
Preparation before removing BackDoor.TeamViewer.49.
Before starting the actual removal process, we recommend that you do the following preparation steps.
- Make sure you have these instructions always open and in front of your eyes.
- Do a backup of all of your files, even if they could be damaged. You should back up your data with a cloud backup solution and insure your files against any type of loss, even from the most severe threats.
- Be patient as this could take a while.
Step 1: Boot Your PC In Safe Mode to isolate and remove BackDoor.TeamViewer.49
Step 2: Clean any registries, created by BackDoor.TeamViewer.49 on your computer.
The usually targeted registries of Windows machines are the following:
- HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
- HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunOnce
- HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce
You can access them by opening the Windows registry editor and deleting any values, created by BackDoor.TeamViewer.49 there. This can happen by following the steps underneath:
Tip: To find a virus-created value, you can right-click on it and click “Modify” to see which file it is set to run. If this is the virus file location, remove the value.Step 3: Find files created by BackDoor.TeamViewer.49
For Windows 8, 8.1 and 10. For Windows XP, Vista, and 7.For Newer Windows Operating Systems
1: On your keyboard press + R and write explorer.exe in the Run text box and then click on the Ok button.
2: Click on your PC from the quick access bar. This is usually an icon with a monitor and its name is either “My Computer”, “My PC” or “This PC” or whatever you have named it.
3: Navigate to the search box in the top-right of your PC’s screen and type “fileextension:” and after which type the file extension. If you are looking for malicious executables, an example may be “fileextension:exe”. After doing that, leave a space and type the file name you believe the malware has created. Here is how it may appear if your file has been found:
N.B. We recommend to wait for the green loading bar in the navination box to fill up in case the PC is looking for the file and hasn’t found it yet.
For Older Windows Operating Systems
In older Windows OS’s the conventional approach should be the effective one:
1: Click on the Start Menu icon (usually on your bottom-left) and then choose the Search preference.
2: After the search window appears, choose More Advanced Options from the search assistant box. Another way is by clicking on All Files and Folders.
3: After that type the name of the file you are looking for and click on the Search button. This might take some time after which results will appear. If you have found the malicious file, you may copy or open its location by right-clicking on it.
Now you should be able to discover any file on Windows as long as it is on your hard drive and is not concealed via special software.
Before starting “Step 4”, please boot back into Normal mode, in case you are currently in Safe Mode.
This will enable you to install and use SpyHunter 5 successfully.
Step 4: Scan for BackDoor.TeamViewer.49 with SpyHunter Anti-Malware Tool
Milena Dimitrova
An inspired writer and content manager who has been with SensorsTechForum since the beginning. Focused on user privacy and malware development, she strongly believes in a world where cybersecurity plays a central role. If common sense makes no sense, she will be there to take notes. Those notes may later turn into articles! Follow Milena @Milenyim
Follow Me:
Preparation before removing BackDoor.TeamViewer.49.
Before starting the actual removal process, we recommend that you do the following preparation steps.
- Make sure you have these instructions always open and in front of your eyes.
- Be patient as this could take a while.
Step 1: Uninstall BackDoor.TeamViewer.49 and related software from Windows
Here is a method in few easy steps that should be able to uninstall most programs. No matter if you are using Windows 10, 8, 7, Vista or XP, those steps will get the job done. Dragging the program or its folder to the recycle bin can be a very bad decision. If you do that, bits and pieces of the program are left behind, and that can lead to unstable work of your PC, errors with the file type associations and other unpleasant activities. The proper way to get a program off your computer is to Uninstall it. To do that:
Follow the instructions above and you will successfully uninstall most programs.Step 2: Clean your Browsers from BackDoor.TeamViewer.49.
Remove an extension from Mozilla Firefox
Remove an extension from Google Chrome
Remove an extension from Internet Explorer
Remove an extension from Microsoft Edge
2. Select the “Add-ons” icon from the menu.
3. Select the unwanted extension and click “Remove“
4. After the extension is removed, restart Mozilla Firefox by closing it from the red “X” button at the top right corner and start it again.
2. Move the cursor over “Tools” and then from the extended menu choose “Extensions“
3. From the opened “Extensions” menu locate the unwanted extension and click on its “Remove” button.
4. After the extension is removed, restart Google Chrome by closing it from the red “X” button at the top right corner and start it again.
2. Click on the gear icon labeled ‘Tools’ to open the drop menu and select ‘Manage Add-ons’
3. In the ‘Manage Add-ons’ window.
4. Select the extension you want to remove and then click ‘Disable’. A pop-up window will appear to inform you that you are about to disable the selected extension, and some more add-ons might be disabled as well. Leave all the boxes checked, and click ‘Disable’.
5. After the unwanted extension has been removed, restart Internet Explorer by closing it from the red ‘X’ button located at the top right corner and start it again.
2. Open the drop menu by clicking on the icon at the top right corner.
3. From the drop menu select “Extensions”.
4. Choose the suspected malicious extension you want to remove and then click on the gear icon.
5. Remove the malicious extension by scrolling down and then clicking on Uninstall.
Step 3: Clean any registries, created by BackDoor.TeamViewer.49 on your computer.
The usually targeted registries of Windows machines are the following:
- HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
- HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunOnce
- HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce
You can access them by opening the Windows registry editor and deleting any values, created by BackDoor.TeamViewer.49 there. This can happen by following the steps underneath:
Tip: To find a virus-created value, you can right-click on it and click “Modify” to see which file it is set to run. If this is the virus file location, remove the value.Before starting “Step 4”, please boot back into Normal mode, in case you are currently in Safe Mode.
This will enable you to install and use SpyHunter 5 successfully.
Step 4: Scan for BackDoor.TeamViewer.49 with SpyHunter Anti-Malware Tool
Milena Dimitrova
An inspired writer and content manager who has been with SensorsTechForum since the beginning. Focused on user privacy and malware development, she strongly believes in a world where cybersecurity plays a central role. If common sense makes no sense, she will be there to take notes. Those notes may later turn into articles! Follow Milena @Milenyim
Follow Me:
Preparation Phase:
Before starting to follow the steps below, be advised that you should first do the following preparations:
- Backup your files in case the worst happens.
- Make sure to have a device with these instructions on standy.
- Arm yourself with patience.
Step 1: Uninstall BackDoor.TeamViewer.49 and remove related files and objects
1. Hit the ⇧+⌘+U keys to open Utilities. Another way is to click on “Go” and then click “Utilities”, like the image below shows:
- Go to Finder.
- In the search bar type the name of the app that you want to remove.
- Above the search bar change the two drop down menus to “System Files” and “Are Included” so that you can see all of the files associated with the application you want to remove. Bear in mind that some of the files may not be related to the app so be very careful which files you delete.
- If all of the files are related, hold the ⌘+A buttons to select them and then drive them to “Trash”.
In case you cannot remove BackDoor.TeamViewer.49 via Step 1 above:
In case you cannot find the virus files and objects in your Applications or other places we have shown above, you can manually look for them in the Libraries of your Mac. But before doing this, please read the disclaimer below:
You can repeat the same procedure with the following other Library directories:
→ ~/Library/LaunchAgents
/Library/LaunchDaemons
Tip: ~ is there on purpose, because it leads to more LaunchAgents.
Step 2: Remove BackDoor.TeamViewer.49 – related extensions from Safari / Chrome / Firefox
Remove an extension from Safari and reset it.Remove a toolbar from Google Chrome Remove a toolbar from Mozilla Firefox
Step 3: Scan for and remove BackDoor.TeamViewer.49 files from your Mac
When you are facing problems on your Mac as a result of unwanted scripts and programs such as BackDoor.TeamViewer.49, the recommended way of eliminating the threat is by using an anti-malware program. Combo Cleaner offers advanced security features along with other modules that will improve your Mac’s security and protect it in the future.
Milena Dimitrova
An inspired writer and content manager who has been with SensorsTechForum since the beginning. Focused on user privacy and malware development, she strongly believes in a world where cybersecurity plays a central role. If common sense makes no sense, she will be there to take notes. Those notes may later turn into articles! Follow Milena @Milenyim
Follow Me:
