The Teamfostealer Trojan is a dangerous weapon used against computer users worldwide. It infects mainly via infected software installers. Our article gives an overview of its behavior according to the collected samples and available reports, also it may be helpful in attempting to remove the virus.
|Short Description||The Teamfostealer Trojan is a computer virus that is designed to silently infiltrate computer systems.|
|Symptoms||The victims may not experience any apparent symptoms of infection.|
|Distribution Method||Software Vulnerabilities, Freeware Installations, Bundled Packages, Scripts and others.|
|Detection Tool|| See If Your System Has Been Affected by Teamfostealer Trojan |
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|User Experience||Join Our Forum to Discuss Teamfostealer Trojan.|
Teamfostealer Trojan – Distribution Methods
The Teamfostealer Trojan is a very dangerous malware which was recently captured in an active campaign. The method of distribution is seen as very effective — the criminal collective behind the Teamfostealer Trojan is currently embedding the Trojan installation code in application installers of one of the most popular system utilities — Team Viewer. This is one of the most widely used solutions for remote logins.
This mechanism is primarily done by taking the real installers and modifying them to include the virus code. The hacking collective will download the legitimate setup file and modify it accordingly. The files are then delivered to the targets using a series of tactics — concentrating on a given approach or using several ones at once in order to maximize the number of possible infected computers.
At the moment the captured samples have been found posted on hacker-controlled sites. This means that some ind of a redirect scheme is being employed in order to lure them into downloading and running the malicious files. There are several popular approaches that can be undertaken:
- Email-based Phishing Campaigns — The hackers can plan an email-based phishing campaign which sends out messages that pose as legitimate notifications by welll-known companies or services. The criminals will spoof the original body design and text layout of the companies which can make it almost impossible to distinguish them from the real ones. The malicious Team Viewer files that contain the Teamfostealer Trojan installation code can be linked in the body contents or directly attached to the emails.
- Malicious Sites — A similar mechanism is the creation and maintenance Internet pages that look like the real landing pages of well-known search engines, download portals, company profiles pages and etc. They are hosted on similar sounding domain names that are very difficult to differentiate from the legitimate ones. Additionally they can include security certificates that can build the feeling that the accessed pages are safe.
- Bundle Downloads — The Teamfostealer Trojan can be embedded in application installers across the Internet. They are very similar to the infected application installers in a sense that they are made by modifying legitimate files with virus code.
- File-sharing networks — BitTorrent and other P2P platforms are very popular at sending both legitimate and pirate content. As such they are among the most dangerous conduits of malware files.
- Browser Hijackers — The infections can also be be caused through the use of dangerous plugins made for the most popular web browsers, alternatively known as hijackers. They are widely available from their associated repositories or download sites and promoted through elaborate descriptions and fake user reviews. When installed they will change the default settings in order to redirect the victims to a hacker-controlled web page. At the same time the virus infection will also be triggered.
Various other methods can be used in future campaigns. Take note that the delivered malicious Team Viewer packages are self-extracting archives (SFX/SEA) which is not the way the vendor has intended it to be. This is yet another warning sign that the package may be malicious in nature.
Teamfostealer Trojan – Detailed Description
The Teamfostealer Trojan will run the typical behavior patterns as observed by many other similar threats. Instead of the legitimate Team Viewer application the dangerous Trojan will be deployed to the systems. The first commands that are to be run will be to drop spyware data inside the User’s temporary folder as files that have typical Windows-related data which doesn’t raise any alarms of suspicion.
The malicious TeamViewer.exe will then load these files and launch a data collection module which will acquire the information and send it to the hacker operators via a network connection. The following information is confirmed to be extracted:
- Operating System
- OS Architecture
- Computer Name
- User Name
- RAM size
- Presence of AV Products
- Administrator Privilege
So far the Trojan has been found to focus mainly on data retrieval, possibly extending this feature to personal information as well. If this is done the engine will be programmed tool acquire strings that can directly expose the identity of the victim users. Such include their names, address, phone number, interests and any stored account credentials. If the Trojan interacts with the Windows Volume Manager it will be able to access removable storage devices and network shares as well. Successful exploitation of this behavior can help facilitate crimes such as identity theft and financial abuse.
Other malicious behavior that can be exhibited includes the execution of other modules in future versions. A common component is the persistent installation — it will set up the infection in such a way that the malicious code will be started every time the computer is powered on. This means that most of the manual user recovery instructions will not work as the virus will disable the access to the recovery menus and boot options.
An associated practice is the launch of a security bypass which will scan the infected machine for the presence of any anti-virus products and actively disable them. This is an effective solution against all services that can block the Trojan’s operations: firewalls, anti-virus products, virtual machine hosts and etc.
One of the most dangerous consequences of having such infections active on a host computer is when additional payloads are delivered. This is a very dangerous scenario as it has already disabled the security on the target computers and all dropped malware will have the ability to unfold all of their capabilities. The forthcoming campaign might contain a radically changed engine that will follow another set of behavior patterns.
Remove Teamfostealer Trojan Trojan
If your computer system got infected with the Teamfostealer Trojan Trojan, you should have a bit of experience in removing malware. You should get rid of this Trojan as quickly as possible before it can have the chance to spread further and infect other computers. You should remove the Trojan and follow the step-by-step instructions guide provided below.
Note! Your computer system may be affected by Teamfostealer Trojan and other threats.
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