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Virus:W32/Redlof

Classification

Category: Malware

Type: Virus

Aliases: Virus:W32/Redlof, VBS/Redlof.A@m, VBS/Redolf

Summary


A malicious program that secretly integrates itself into program or data files. It spreads by integrating itself into more files each time the host program is run.

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


Redlof (also detected as VBS/Redlof.A@m) is a polymorphic virus that embeds itself without any attachment to every email sent from the infected system. It executes when an infected email message is viewed.Redlof executes directly from an infected message by using a security vulnerbility in Internet Exlorer known as Microsoft VM ActiveX Control Vulnerability. More information about the vulnerability and a fix is available from Microsoft:

  • https://www.microsoft.com/technet/security/bulletin/ms00-075.asp
Infection

When the virus executes, it infects a file "web\Folders.htt" at the Windows installation directory which causes that the virus activates when any directory is opened using the Active Desktop's web folder feature.The virus also infects files with extensions:

  • "htm"
  • "html"
  • "asp"
  • "php"
  • "jsp"
  • "htt"
  • "vbs"

Redlof drops the following infected files:

  • \Program Files\Common Files\Microsoft Shared\Stationery\blank.html
  • \Windows\System\Kernel32.dll
  • \Windows\web\kjwall.gif
  • \Windows\system32\desktop.ini

"blank.html" is used to replace the default stationaries for both Outlook and Outlook Express via registry causing that the every message sent from an infected system will carry the virus.The "Kernel32.dll" is also set to registry so that it will be executed on the system restart.