In the last months, the world has been shocked by two major cyber-attacks. In the first attack that took place in May, more than 200,000 computers in 150 countries were controlled by WannaCry, a ransom program. The British healthcare system was on the verge of collapse. The destructive effect of the program was hardly stopped in two days. After the attack, it was found that WannaCry controlled computers through an exploit that National Security Agency had previously found in Microsoft’s software. Hackers carried out the cyber-attack by developing a program that took advantage of this exploit.
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