The Top 10 Worst Pc Viruses Of All Time Вђ“ Azmath May 2026

: A sophisticated worm that created a massive botnet of millions of infected Windows computers, targeting government and business servers.

: A fast-spreading worm that caused roughly $30 billion in damage by overloading corporate servers with millions of emails.

: A worm that exploited a vulnerability in Microsoft IIS web servers to launch DDoS attacks, including one targeting the White House website.

: A massive ransomware attack that encrypted files and demanded Bitcoin payments, famously crippling the UK's National Health Service.

: A tiny but powerful worm that slowed the entire internet to a crawl in just minutes by targeting SQL servers.

: An advanced Trojan horse used to steal banking information, reportedly affecting 88% of Fortune 500 companies.