WannaCry to SamSam: 5 biggest ransomware attacks you need to know about

The computer servers at the All India Institute of Medical Sciences (AIIMS), Delhi, have been down for seven days. Media reports stated that this might have been a hack, and data of around 3-4 crore users stood exposed. On Monday evening, PTI reported that the servers were hit by ransomware, and the hackers demanded Rs 200 crore in cryptocurrency from the hospital.

Later in the evening, Delhi Police refuted the claims and stated that there was no such demand. 

Ransomware attacks have been taking place for a long time, but their frequency has increased in the last few years

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