What is a ransomware attack?
Ransomware is a form of malicious software — malware — which encrypts documents on a PC or even across a network. Victims can often only regain access to their encrypted files and PCs by paying a ransom to the criminals behind the ransomware.
A ransomware infection often starts with someone clicking on what looks like an innocent attachment, and it can be a headache for companies of all sizes if vital files and documents (think spreadsheets and invoices) are suddenly encrypted and inaccessible. But that’s not the only way to get infected.
What is the history of ransomware?
While ransomware exploded last year, increasing by an estimated 748 percent, it’s not a new phenomenon: the first instance of what we now know as ransomware appeared in 1989.
Known as AIDS or the PC Cyborg Trojan, the virus was sent to victims — mostly in the healthcare industry — on a floppy disc. The ransomware counted the number of times the PC was booted: once it hit 90, it encrypted the machine and the files on it and demanded the user ‘renew their license’ with ‘PC Cyborg Corporation ‘ by sending $189 or $378 to a post office box in Panama.
How did ransomware evolve?
This early ransomware was a relatively simple construct, using basic cryptography which mostly just changed the names of files, making it relatively easy to overcome.
But it set off a new branch of computer crime, which slowly but surely grew in reach — and really took off in the internet age. Before they began using advanced cryptography to target corporate networks, hackers were targeting general internet users with basic ransomware.
One of the most successful variants was ‘police ransomware’, which tried to extort victims by claiming to be associated with law enforcement. It locked the screen with a ransom note warning the user they’d committed illegal online activity, which could get them sent to jail.
However, if the victim paid a fine, the ‘police’ would let the infringement slide and restore access to the computer by handing over the decryption key.
What are the main types of ransomware?
Ransomware is always evolving, with new variants continually appearing in the wild and posing new threats to businesses. However, there are certain types of ransomware which have been much more successful than others.
Perhaps the most notorious form of ransomware is Locky, which terrorised organizations across the globe throughout 2016. It infamously made headlines by infecting a Hollywood hospital. The hospital gave into the demands of cybercriminals and paid a $17,000 ransom to have its networks restored.
Locky remained successful because those behind it regularly update the code to avoid detection. They even update it with new functionality, including the ability to make ransom demands in 30 languages, so criminals can more easily target victims around the world. Locky became so successful, it rose to become most prevalent forms of malware in its own right.
Cryptowall is another form of ransomware which has found great success for a prolonged period of time. Starting life as doppelganger of Cryptolocker, it’s gone onto become one of the most successful types of ransomware.
One of the most common forms of ransomware distributed in this way is Cerber, which infected hundreds of thousands of users in just a single month. The original creators of Cerber are selling it on the Dark Web, allowing other criminals to use the code in return for 40 percent of each ransom paid.
Cerber ransomware became so successful that it surpassed Locky — which appeared to mysteriously disappear over Christmas, although reemerged in April with new attack techniques — to become the most dominant form of ransomware on the web, accounting for 90 percent of ransomware attacks on Windows as of mid-April 2017.
The cryptography behind Cerber is so advanced that there’s currently no decryption tools available to help those infected by the latest versions.
Cerber now comes with the ability to steal to steal bitcoin wallet and password information, in addition to encrypting files.
In exchange for giving up some of the profits for using Cerber, wannabe cyber-fraudsters are provided with everything they need in order to successfully make money through the extortion of victims.
What is WannaCry ransomware?
In the biggest ransomware attack to date, WannaCry — also known as WannaCrypt and Wcry — caused chaos across the globe in an attack which started on Friday 12 May 2017. WannaCrypt ransomware demands $300 in bitcoin for unlocking encrypted files — a price which doubles after three days. Users are also threatened, via a ransom note on the screen, with having all their files permanently deleted if the ransom isn’t paid within a week.
More than 300,000 victims in over 150 countries fell victim to the ransomware over the course of one weekend, with businesses, governments, and individuals across the globe all affected.
Healthcare organisations across the UK had systems knocked offline by the ransomware attack, forcing patient appointments to be cancelled and hospitals telling people to avoid visiting Accident and Emergency departments unless it was entirely necessary.
Of all the countries affected by the attack, Russia was hit the hardest, according to security researchers, with the WannaCry malware crashing Russian banks, telephone operators, and even IT systems supporting transport infrastructure. China was also hit hard by the attack, with 29,000 organizations in total falling victim to this particularly vicious form of ransomware.
Other high-profile targets included the car manufacturer Renault which was forced to halt production lines in several locations as the ransomware played havoc with systems.
What all the targets had in common is that they were running unsupported versions of Microsoft Windows, including Windows XP, Windows 8, and Windows Server 2003.
The ransomware worm is so potent because it exploits a known software vulnerability called EternalBlue. The Windows flaw is one of many zero-days which apparently was known by the NSA — before being leaked by the Shadow Brokers hacking collective. Microsoft released a patch for the vulnerability earlier this year — but only for the most recent operating systems.
In response to the attack, Microsoft took the unprecedented step of issuing patches for unsupported operating systems to protect against the malware.
It was almost three months before the WannaCry attackers finally withdrew the funds from the WannaCry bitcoin wallets — they made off with a total of $140,000 thanks to fluctuations in the value of bitcoin.
But despite critical patches being made available to protect systems from WannaCry and other attacks exploiting the SMB vulnerability, a large number of organisations seemingly chose not to apply the updates.
But that’s a relatively modest loss in comparison to other victims of the attack: shipping and supply vessel operator Maersk and goods delivery company FedEx have both estimated losses of $300m due to the impact of Petya.
In February 2018, the governments of the United Kingdom, the United States, Australia and others officially declared that the NotPetya ransomware had been the work of the Russian military. Russian denies any involvement.
What is Bad Rabbit ransomware?
October 2017 saw the third high profile ransomware attack of the year when organizations in Russia and Ukraine fell victim to a new variant of Petya ransomware.
Dubbed Bad Rabbit, it infected at least three Russian media organisations while also infiltrating the networks of several Ukrainian organisations including the Kiev Metro and Odessa International Airport – at the time, the airport said it had fallen victim to a ‘hacker attack’.
The initial attack vector used to distribute Bad Rabbit was drive-by downloads on hacked websites – some of which had been compromised since June. No exploits were used, rather visitors were told they had to install a phony Flash update, which dropped the malware.
Like NotPetya before it, Bad Rabbit spread through networks using a leaked NSA hacking tool – but this time it was via the EternalRomance SMB vulnerability, rather than the EternalBlue exploit.
Analysis of Bad Rabbit shared much of its code – at least 67 percent – with Peyta and researchers at Cisco Talos concluded that this, combined with how it uses SMB exploits, means there’s “high confidence” in a link between the two forms of ransomware – and that they could even share the same author.
Bad Rabbit was named after the text which appeared at the top of the Tor website hosting the ransom note. Some security researchers joked it should’ve been named after the lines in the code referencing characters from Game of Thrones.
How do you prevent a ransomware attack?
With email being by far the most popular attack vector for ransomware, you should provide employees with training on how to spot an incoming malware attack. Even picking up on little indicators like poor formatting or that an email purporting to be from ‘Microsoft Security’ is sent from an obscure address which doesn’t even contain the word Microsoft within it might save your network from infection. The same security policies that protect you from malware attacks in general will go some way towards protecting your company from ransom demands too.
At the very least, employers should invest in antivirus software and keep it up-to date, so that it can warn users about potentially malicious files. Backing up important files and making sure those files can’t be compromised during an attack in another key.
How long does it take to recover from a ransomware attack?
Simply put, ransomware can cripple a whole organization — an encrypted network is more or less useless and not much can be done until systems are restored.
If your organization is sensible and has backups in place, systems can be back online in the time it takes the network to be restored to functionality, although depending on the size of the company, that could range from a few hours to days.
FedEx said that it may not be able to recover all the systems affected by the Petya cyberattack, meaning that while the company is back up and running, some machines won’t ever be able to be restored.
Outside of the immediate impact ransomware can have on a network, it can result in an ongoing financial hit.
How do I get rid of ransomware?
The ‘No More Ransom’ initiative — launched in July 2016 by Europol and the Dutch National Police in collaboration with a number of cybersecurity companies including Kaspersky Lab and McAfee — offers free decryption tools for ransomware variants to help victims retrieve their encrypted data without succumbing to the will of cyber extortionists.
Initially launching as a portal offered portal offers decryption tools four for families of ransomware — Shade, Rannoh, Rakhn, and CoinVault — the scheme is regularly adding more decryption tools for even more versions of ransomware including Crypt XXX, MarsJoke, Teslacrypt, Wildfire and Nemucod.
The portal — which also contains information and advice on avoiding falling victim to ransomware in the first place — is updated as often as possible in an effort to ensure tools are available to fight the latest forms of ransomware.
No More Ransom has grown from offering a set of four tools to carrying 52 decryption tools covering hundreds of families of ransomware. So far, these tools have decrypted tens of thousands of devices, depriving criminals of millions in ransoms.
The platform is now available in over 29 languages with more than 100 partners across the public and private sectors supporting the scheme.
Individual security companies also regularly release decryption tools to counter the ongoing evolution of ransomware — many of these will post updates about these tools on their company blogs as soon as they’ve cracked the code.
A decryption tool was recently released which may be able to help if your PC has been hit by one of the original versions of the Petya malware — the so-called Red Petya, Green Petya, and GoldenEye — and may enable you to recover the lost files (although it can’t help with PetrWrap or those hit by the Petya/NotPetya global attack). However, these tools don’t always work so it is always wise to make additional backups.
Another way of working around a ransomware infection is to ensure your organization regularly backs up data offline.
Should I pay a ransomware ransom?
There are those who say victims should just pay the ransom, citing it to be the quickest and easiest way to retrieve their encrypted data — and many organizations do pay even if law enforcement agencies warn against it.
WARNING: if word gets out that your organization is an easy target for cybercriminals because it paid a ransom, you could find yourself in the crosshairs of other cybercriminals who are looking to take advantage of your weak security.