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Small.QP

Classification

Category: Malware

Type: Trojan-Dropper

Aliases: Small.QP

Summary


Small.QP copies itself to the Windows folder and attempts to download and install other malware to the system.

Removal


Automatic action

Based on the settings of your F-Secure security product, it will either automatically delete, quarantine or rename the detected program or file, or ask you for a desired action.

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Technical Details


Upon execution, this malware creates the mutex _Win_Loader_ to ensure that only one instance of itself is running in memory.Additionally, it drops the following files in the affected system:

  • %windir%\winlogon32.exe - A copy of itself (Detected as Trojan-Dropper.Win32.Small.qp)
  • %windir%\winlogon32.dll - Another malware file (Detected as Trojan-Downloader.Win32.Small.anj)
  • %windir%\prefoct.dat - An empty file

As a stealth mechanism, it loads the dropped DLL, winlogon32.dll, under the legitimate process: lsass.exe.Trojan-Downloader.Win32.Small.anj, on the other hand, creates the mutex _Win_Loader__Win_Loader_. This malware attempts to connect to the following web sites to possibly download other malicious components:

  • https://www.max-stats.com/l/[REMOVED].php?i=21 Data downloaded is saved in the file, %windir%\prefoct.dat
  • https://www.teen4-sex.com/[REMOVED].dat Data downloaded is saved in the file, %wndir%\_tmp0232.exe

Small.QP then executes the downloaded file, _tmp0232.exe. Note: Both download sites are unavailable at the time of writing.There are additional details on Small.QP on F-Secure's Weblog.