The UK NHS yesterday reported a large-scale cyber attack that forced trusts across the country to shut down their entire IT systems and postpone all non-urgent activity.
The attack is believed to be the result of "ransomware", a type of malware that been used by computer hackers for many years to capture information, extort money or force people or organisations to behave in certain ways.
It's one of a number of different tools that cybersecurity specialists have to fight against, in order to keep systems safe.
Worryingly, ransomware and virus programs are becoming increasingly widespread. Would-be hackers can purchase malicious software kits the same way they would buy a video game or creative design program.
What is a Crypto- Ransomware?
How does ransomware work?
Ransomware gains access to a computer the same way as any kind of virus or computer worm - either through getting the user to open an infected email, navigate to a compromised website or install an infected program.
Once inside a computer it can work in a several different ways. One of these is to bombard users with adverts, indecent images or bogus warnings until they pay to have them removed.
Alternatively, it can lock users out of one or more parts of their PC until they pay to have access restored. Sometimes it does this by mimicking an official warning from a government agency or police force.
Finally, there is the method mentioned above - where personal or important files are removed from the host PC, encrypted and threatened with deletion.
Victims are often given a time limit within which to pay and ransoms can vary in price from tens to hundreds of pounds.
Often ransoms are demanded in an untraceable cryptocurrency, such as Bitcoin, to make them harder for law enforcement to trace.
Should the ransom ever be paid?
"Paying it will just be the start of your problems – remember that the people who do this are criminals," said Guy Bunker, a senior vice president of products at information security company Clearswift.
The sentiment is echoed by other security experts.
Brian Kennedy from US security consultancy iSight said that paying up won't guarantee you'll regain control of your device or files.
"Some ransomware operators will refuse to unlock your device even after you've paid, and demand more money or attempt to defraud you by other means with the financial information you've provided them," Kennedy added.
The problem is that the more people pay the ransom, the more of an incentive cybercriminals have to use this technique since it offers "easy profit".
It's better to backup your files and use strong antivirus software instead.
What can YOU do to protect yourself?
Read our next post to get some helpful tips to protect yourself from Crypto - Ransomware