Downloader-AXK

Downloaders are designed to pull files from a remote website and execute the files that have been downloaded.

It is trivial for the malware author to modify the Downloader to refer to a different website or web address. Therefore, it is not possible to guarantee which website and/or port is being communicated with.

Also, as the website being communicated with is normally controlled by the malware author, any files being downloaded can be remotely modified and the behaviour of these new binaries altered - possibly with every user infection.

Upon execution it makes internet connection in the background with ?www.mrfind[Removed].com? and downloads some files without user?s knowledge.

Following files are added:

•  ftuninst.exe (Detected as Adware-LinkMaker)
• ssec.exe (Detected as Loader-B) 
• tfthot.exe (Detected as Adware-LinkMaker.dldr)
• gbe90qs.exe (Detected as Adware-LinkMaker.dldr)
• mptft.exe (Detected as Adware-LinkMaker)
• nr1rnqm8.exe
• ssn6tuu.exe (Detected as Adware-LinkMaker.dldr)
• x3cqp0.dll (Detected as Adware-LinkMaker)

The following registry entries are added in order to run the trojan on the system startup

• HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\
  CurrentVersion\Run "ftexc"
• HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\
  CurrentVersion\Run "Hhl7RfpJ"

It adds the following Browser Helper Objects for the Interent Explorer

• HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\
  CurrentVersion\Explorer\Browser Helper Objects\
  {AE0ECC2F-0C33-494C-8B22-B57A7763027F}
• HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\
  CurrentVersion\Explorer\Browser Helper Objects\
  {E5E2A3E7-00FE-4D31-A030-A10799DDCA66}

Browser Helper Objects are executable files that are loaded when the browser is launched. They can perform various tasks, such as generating extra pop-up ads, monitoring page navigation, etc

It also adds the following registry entries

• HKEY_CLASSES_ROOT\CLSID\
  {AE0ECC2F-0C33-494C-8B22-B57A7763027F}
• HKEY_CLASSES_ROOT\CLSID\
  {DA28E0DB-229C-4003-827E-96AE15AD90FB}
• HKEY_CLASSES_ROOT\Fseytdc.Ariaqudok
• HKEY_CLASSES_ROOT\Fseytdc.Ariaqudok.1
• HKEY_CLASSES_ROOT\Fseytdc.Yvakt
• HKEY_CLASSES_ROOT\Fseytdc.Yvakt.1
• HKEY_CLASSES_ROOT\Interface\
  {34E97B51-AB15-419B-96D1-1B2469659004}
• HKEY_CLASSES_ROOT\TypeLib\
  {1EA4DBF0-3C3B-11CF-810C-00AA00389B71}
• HKEY_CLASSES_ROOT\TypeLib\
  {5769647E-6937-4390-BC5A-F5A986CAA1F2}

Presence of aforementioned files and registry entries

Downloaders are not viruses, and as such do not themselves contain any method to replicate. However they may themselves be downloaded by other viruses and/or Trojans to be installed on the user's system.

Many of these additionally are mass spammed by the author to entice people into double-clicking on them.

Alternatively they may be installed by visiting a malicious web page (either by clicking on a link, or by the website hosting a scripted exploit which installs the Downloader onto the user's system with no user interaction.

A combination of the latest DATs and the Engine will be able to detect and remove this threat. AVERT recommends users not to trust seemingly familiar or safe file icons, particularly when received via P2P clients, IRC, email or other media where users can share files.