What computer virus holds the record for being the most widespread computer virus?

The correct answer is I Love You because the ILOVEYOU worm (often categorized broadly as a virus in historic literacy exams) infected over 10 million Windows personal computers within days of its launch in May 2000.

• Step 1 (Historical Impact): Originating in the Philippines, the malware spread through an email with the subject line 'ILOVEYOU' containing a malicious attachment disguised as a harmless text file (LOVE-LETTER-FOR-YOU.TXT.vbs).
• Step 2 (Widespread Damage): Once executed, it automatically forwarded itself to every contact in the user's Microsoft Outlook address book, resulting in estimated global damages of up to billion and shutting down government and corporate email servers worldwide.
• Incorrect Options:
  • Nimda is incorrect because while Nimda was a highly aggressive and complex multi-vector worm launched in 2001, it did not surpass the historic sheer footprint or cultural saturation of the ILOVEYOU campaign.
  • Melissa is incorrect because Melissa was an earlier macro-based email virus launched in 1999 that laid the groundwork for future mass-mailers but infected significantly fewer total machines.
  • Conficker is incorrect because Conficker was a sophisticated 2008 network botnet worm that targeted specific unpatched operating system vulnerabilities rather than achieving the record-breaking social engineering explosion seen in 2000.