Virus:W32/Redlof

Classification

Malware

Virus

W32

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.

Automatic action

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.

Suspect a file is incorrectly detected (a False Positive)?

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 detection database 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.

For more Support

Knowledge Base

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User Guide

See the user guide for your product on the Help Center.

Contact Support

Chat with or call an expert for help.

Submit a sample

Submit a file or URL for further analysis.

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.