The biggest ransomware attacks: How has ransomware affected businesses around the world?
Ransomware is a type of malicious software that will block access to your network and threaten to delete your files unless you pay a ransom.
The most common, and destructive type of ransomware is 'Locky', which comes in the form of a document that requires the recipient enables macros. Once this is done, a download will begin and when complete it will scramble your data and demand payment for it to be released. Most payments will be demanded in Bitcoin as it's less traceable.
However, this month WannaCry ransomware has been thrust into the headlines after it infected hundreds of businesses across the globe, including 47 Trusts within NHS England.
A ransomware attack isn't necessarily a very costly operation, with most hackers demanding around $600 (£465) to release files, but they can highlight the vulnerabilities within organisations, depicting a lack of funding, security procedures and infrastructure in place.
We look at some of the most damaging ransomware attacks in history...
1. The NHS
NHS England was the victim of a massive ransomware attack on 12 May, resulting in 47 Trusts becoming infected and even some patients' operations being cancelled as a result.
The USA's National Security Agency initially discovered an exploit in Microsoft's EternalBlue software. The vulnerability which left older Microsoft systems such as Windows XP (which the majority of NHS Trusts used) open to attacks was leaked by a hacker group called the Shadow Brokers earlier this year but was patched by Microsoft at the time.
The type of ransomware that infected NHS England - along with numerous government institutions in China, Russia, the US and most of Europe - is called WannaCry or WannaCrypt and works like most ransomware, deliverable to the user via an email requesting them to download something, which will infect their system with ransomware.
Other organisations affected include FedEx, Deutsche Bahn and Telefonica. Although, according to Telefonica, the disruption from its attack was limited, only affecting computers on their internal network, leaving client services free from infection.
2. Russia's Interior Ministry
Russia confirmed that its Interior Ministry was targeted by the WannaCry ransomware on 14 May, resulting in 1,000 infected computers.
According to Russian anti-virus firm Kaspersky Lab, the ransomware attempted to access more computers in Russia than anywhere else in the world.
In total, the interior ministry, railways, banks and Russia's second largest mobile carrier Megafon were all affected by the attacks.
According to an interior ministry spokesperson, while its computers were affected, its servers were safe, as they run a Russian OS called Elbrus, specifically created for and by the Soviet Union, the New York Times reported.
3. Nissan and Renault
Car manufacturers Nissan and Renault's systems were impacted massively by the WannaCry ransomware too, with production halting and systems slowing down.
Renault was the first major French company to announce that it was suffering from the ransomware attack. This led Renault to halt car production across most if its European facilities in an attempt to prevent further spread of the malware.
A spokesperson for Renault said on Sunday (14 May) that most plants will be resuming normal activity from Monday.
Similarly, Nissan - which is part of Renault's Alliance - was also affected by the ransomware attack, which resulted in the car manufacturer's Sunderland factory being forced to stop production, although the Nissan spokesperson didn't explicitly confirm a total shutdown, instead only confirming that it was affected by the global ransomware attack.
A collection of ransomware attacks hit businesses using MongoDB early this year, putting nearly 100,000 databases at risk.
MongoDB, an open-source database system, was a victim of a damaging ransomware attack in which hackers exploited unsecured MongoDB databases and demanded 0.2 Bitcoin (£170 at the time) to return the data it had encrypted.
The initial flaw was uncovered by GDI Foundation's Victor Gevers in December last year, but by January 2017, multiple groups are thought to be involved.
The first attack was thought to be carried out by the hacker Harak1r1, however, since then a number of copycat attacks from different hackers have happened.
5. Churches in Bristol
A number of churches fell victim to ransomware attacks in May 2016, when 46 were infected throughout Bristol, Bath and parts of the greater Gloucestershire area.
The initial infection came about when the church group posted a job advertisement, the hacker then sent an email asking the church to open an attachment of their CV, which triggered the download of the ransomware.
In response the church group contacted the police, refusing to pay the ransom and consequently, lost all of the captured data.
One of the UK's largest managed cloud computing and virtual desktop services was held to ransom in September last year when its files were seized as part of a new strain of ransomware called Samas DR.
The hackers demanded 29 Bitcoins from VESK, totalling £18,600 at the time.
The ransomware infected one of VESK's multi-tenanted environments which supported around 15 percent of its clients.
At the time, Nigel Redwood, chief exec of VESK's parent company, Nasstar, described the process taken to limit the effect, including restoring backups and paying the ransom to get the files decrypted.
"We decided to do that by running restores from backups and also paying for the decryption keys, to attack the problem from both angles," he said.
7. Bournemouth University
Bournemouth University was hit by 21 separate ransomware attacks in 2015 and 2016, as revealed by Freedom of Information requests made by two cyber security firms, SentinelOne and NCC Group.
Bournemouth University confirmed the attacks stating: "It is not uncommon for universities to be the target of cyber security attacks; there are security processes in place at Bournemouth University to deal with these types of incident," according to the BBC.
8. Queen’s University Belfast and Ulster University
Both Ulster University and Queen's University Belfast have suffered ransomware attacks, with both taking very different approaches to resolving the issue.
Freedom of Information requests revealed that Queen's University suffered three ransomware attacks during 2016. In one instance it paid £400 ransom after its computers running Windows XP were exploited, resulting in documents being encrypted.
Conversely, Ulster University discovered 22 ransomware attacks from 2015 to 2016 on personal devices, and the university network being affected on occasion. During all the ransomware attacks, this university did not pay out and instead restored the data.
9. New York Times and BBC
The New York Times and the BBC fell victim to ransomware malvertising along with AOL and the NFL in March last year after multiple ad networks' vulnerabilities were exploited by ransomware.
The attack, which was targeted at US users, was discovered by cyber security firm Malwarebytes, and delivered ransomware to the sites combined millions of users via ad networks that were suffering from flaws from Microsoft's Silverlight, which it stopped supporting in 2013.
The malicious campaign displayed ads redirected users to servers that hosted malware which then tried to locate any vulnerability, or way into users' systems, locking documents and demanding money.
10. Mr Chow's
Popular Chinese restaurant chain Mr Chow's fell victim to a ransomware attack in September 2016, in which the hackers demanded $700 (£540) for customers' data.
Mr Chow's, which has restaurants in London and the US, was using an outdated CMS system which enabled hackers to trigger the Neutrino exploit kit, infecting vulnerable systems with ransomware, according to Malwarebytes.
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