The Morris worm is literally the grand-daddy when it comes to buffer-overflows: https://en.wikipedia.org/wiki/Morris_worm https://en.wikipedia.org/wiki/Morris_

The Morris worm is literally the grand-daddy when it comes to buffer-overflows: https://en.wikipedia.org/wiki/Morris_worm https://en.wikipedia.org/wiki/Morris_worm After that you could see something like SQL Slammer as having a significant impact: https://en.wikipedia.org/wiki/SQL_Slammer https://en.wikipedia.org/wiki/SQL_Slammer But from a technical perspective most of them are much of a muchness - I'm more interested in the first time "things" were written up, such as "Smashing The Stack For Fun And Profit": http://insecure.org/stf/smashstack.html http://insecure.org/stf/smashstack.html Or the first time that Format string attacks were documented - a whole class of vulnerabilities sprang up overnight (my memory is that wu-ftp was the original target there). http://www.drdobbs.com/when-format-strings-attack/184405774 http://www.drdobbs.com/when-format-strings-attack/184405774