Dubai: Ransomware attacks have soared five-fold to hit 718,536 users in one year (between April 2015 and March 2016) and have become a huge problem for cybersecurity over the last few years.

Ransomware affected 54 per cent of attacked users in April 2016 and 35.7 per cent in May, still well above the average for the previous 12 months.

Ransomware is software that infects a smartphone or computer and prevents a users from accessing their data unless the user pays a ransom.

Cyber security experts are saying ransomware is a lucrative and safe method of making money for criminals.

“The biggest problem with ransomware today is that sometimes the only way to get the encrypted data back is to pay the criminals, and victims tend to pay. That brings a lot of money into the underground ecosystem that has grown up around this malware, and as a result we are seeing new cryptors appear almost daily,” he said.

Kaspersky Lab said that the total number of users encountering any type of ransomware increased from 1.97 million to 2.31 million users around the world.

Fedor Sinitsyn, senior malware analyst at Kaspersky Lab, said that ransomware is one of the most dangerous types of malware ever created and it has become so widespread that it could easily be called an epidemic.

In October 2015, ransomware achieve an all-time-high with more than 428.4 thousand users attacked. Of those affected, 9.38 per cent — almost 40 thousand — were hit with encryption ransomware, the most difficult type of ransomware to fix. In March 2016, when another surge of ransomware attacks took place, the situation was very different: over half (51.9 per cent) of those encountered the ‘Trojan-Ransom’ malware, another encryption-based piece of malware.

The cost of decryption varies — from as little as $30 to thousands of dollars. The average ransom demanded by cybercriminals is $300, and according to various sources, at least 40 per cent of the victims pay their ransom.

Sinitsyn said that India, Brazil, Russia and Germany lead the list of countries with the biggest growth in the number of attacked users, while the number in the US, Vietnam, Algeria, Ukraine and Kazakhstan has notably decreased.

Hassam Sidani, regional manager for Symantec Gulf, said the UAE was the fourth most impacted country in the Middle East and Africa region last year when it came to ransomware attacks, and 34th globally.

He said that victims were asked to pay between $50 and $500 (Dh1,850), depending on the data.