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W32/Alcra-F

Aliases
  • Email-Worm.Win32.VB.an
  • W32.Spybot.Worm
  • TROJ_MULDROP.CV
Category
Type
What to do
Prevalence low high

Summary

 
How it spreads
  • Network shares
Affected operating systems Windows
Characteristics
  • Drops more malware
  • Installs itself in the registry
Protection available since 28 March 2006 14:26:39 (GMT)
Detected by All Sophos products
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Action

More Information

W32/Alcra-F is a worm for the windows platform.

W32/Alcra-F uses file sharing applications to spread.

W32/Alcra-F typically arrives with the filename Setup.exe. W32/Alcra-F is a worm for the windows platform.

W32/Alcra-F uses file sharing applications to spread.

W32/Alcra-F typically arrives with the filename Setup.exe.

When first run W32/Alcra-F displays a dialog box with the text "Setup", "Welcome to the Setup Wizard ...".

The dialog then gives a fake error message, before closing.

W32/Alcra-F creates the folder <Program Files>\winsupdater and copies itself to this folder as

a.temp
winsupdater.exe

winsupdater.exe has the hidden file attribute and similarly the
<Program Files>\winsupdater\ folder is a hidden folder.

W32/Alcra-F creates the following files:

<root folder>\at.exe
<Program Files>\winsupdater\a.zip

Where the a.zip file contains a copy of the Setup.exe.
The file at.exe is detected as W32/Rbot-CVY.

When first run, W32/Alcra-F creates the following registry entry to ensure that it is run when an infected system starts:

HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
winsupdater
<Program Files>\winsupdater\winsupdater.exe /auto

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