Update (9:35 a.m.): Updated with Wednesday market open information.
The stock was down 18.65% to $30.20 at 9:35 a.m. on Wednesday.
He noted that many of the attacks you are seeing are because of computers are still using Windows XP.
Shares of many cybersecurity companies were already up strongly over the last 12 months.
Cybersecurity companies benefit from spread of ransomware attack, but can they last?