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  3. W32.Nimda.E@mm


Risk Level 2: Low

October 29, 2001
February 13, 2007 11:37:37 AM
Also Known As:
I-Worm.Nimda.e [Kaspersky], PE_NIMDA.E [Trend], Win32.Nimda.E [Computer Associ, W32/Nimda-D [Sophos], W32/Nimda.E@mm [Frisk], Win32/Nimda.E worm [ESET], W32/Nimda.gen@MM [McAfee]
Worm, Virus
Systems Affected:
Microsoft IIS, Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows XP
CVE References:
CVE-2001-0154 CVE-2000-0884

W32.Nimda.E@mm is a new version of W32.Nimda.A@mm that contains bug fixes and other modifications, which are designed to prevent antivirus programs from detecting this variant.

For additional information, read the Microsoft TechNet article, "Information on the "Nimda" Worm."

For information on .enc detections, read the article, "What is an .enc detection?"

Antivirus Protection Dates

  • Initial Rapid Release version October 29, 2001
  • Latest Rapid Release version February 25, 2015 revision 072
  • Initial Daily Certified version October 29, 2001
  • Latest Daily Certified version February 24, 2015 revision 048
  • Initial Weekly Certified release date October 29, 2001
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

Threat Assessment


  • Wild Level: Low
  • Number of Infections: More than 1000
  • Number of Sites: More than 10
  • Geographical Distribution: High
  • Threat Containment: Moderate
  • Removal: Moderate


  • Damage Level: Medium


  • Distribution Level: High
Writeup By: Eric Chien

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