Downloader-AWS

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 the following file is downloaded:

• documents3072.exe (detected as BackDoor-DIK)

Following registry entries are added:

• HKEY_CLASSES_ROOT\Interface\{03022430-abc4-11d0-bde2-00aa001a1953}
• HKEY_CLASSES_ROOT\TypeLib\
  {1EA4DBF0-3C3B-11CF-810C-00AA00389B71}
  

Presence of aforementioned file and registry keys

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.