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  3. Trojan.Cidox


Risk Level 1: Very Low

July 7, 2011
July 7, 2011 12:03:20 PM
Systems Affected:
Windows 2000, Windows 7, Windows 95, Windows 98, Windows Me, Windows NT, Windows Server 2003, Windows Server 2008, Windows Vista, Windows XP
Trojan.Cidox is a Trojan horse that modifies the NTFS boot sector's Initial Program Loader (IPL) in order to perform malicious actions.

Antivirus Protection Dates

  • Initial Rapid Release version July 7, 2011 revision 007
  • Latest Rapid Release version November 17, 2014 revision 039
  • Initial Daily Certified version July 7, 2011 revision 017
  • Latest Daily Certified version November 19, 2014 revision 034
  • Initial Weekly Certified release date July 13, 2011
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

Threat Assessment


  • Wild Level: Low
  • Number of Infections: 0 - 49
  • Number of Sites: 0 - 2
  • Geographical Distribution: Low
  • Threat Containment: Easy
  • Removal: Easy


  • Damage Level: Medium
  • Payload: Modifies HTML within the Web browser.
  • Modifies Files: Modifies the NTFS boot sector's Initial Program Loader (IPL)


  • Distribution Level: Low
Note: On May 14, 2015, modifications will be made to the threat write-ups to streamline the content. The Threat Assessment section will no longer be published as this section is no longer relevant to today's threat landscape. The Risk Level will continue to be the main threat risk assessment indicator.
Writeup By: Stephen Doherty, Masaki Suenaga, and Takayoshi Nakayama

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