Trojan-Downloader:W32/Agent.FDS

Classification

Category :

Malware

Type :

Trojan-Downloader

Aliases :

Trojan-Downloader:W32/Agent.FDS

Summary

This malware may arrive in the system as a dropped file of other trojan installation packages or may be downloaded from the Internet. When running, this malware will download and execute another trojan in the infected system.

Removal

Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.

A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:

  • Check for the latest database updates

    First check if your F-Secure security program is using the latest updates, then try scanning the file again.

  • Submit a sample

    After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.

    Note: If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.

  • Exclude a file from further scanning

    If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.

    Note: You need administrative rights to change the settings.

Technical Details

On execution, it will initially check to determine if it is running within a virtual machine and exits if this has been satisfied.It will also attempt to disable the computer's System Restore before creating its own copy to avoid the machine being reverted back to a clean state.A modified copy of itself is then created in window's system directory (usually c:\windows\system32) using any of the following filenames:

  • csr[Random].exe
  • ctf[Random].exe
  • drv[Random].exe
  • dsk[Random].exe
  • hlp[Random].exe
  • lsa[Random].exe
  • man[Random].exe
  • mod[Random].exe
  • mon[Random].exe
  • net[Random].exe
  • sql[Random].exe
  • svc[Random].exe
  • sys[Random].exe
  • tsk[Random].exe
  • upd[Random].exe
  • win[Random].exe

It then sets its security attributes to enable only "Traverse Folders / Execute File" (Effective Permissions), thus preventing the user from easily deleting the malware file from the system.If an Internet connection is detected, the malware then downloads and execute another file from:

  • hzzxhngnh.ws
  • rm6ojqab7.info

It downloads to the computer's temporary folder. As of testing however, the said domains are no longer active.