Ransomware accounted for a quarter of the threats aimed at UK computer users over the past week, according to data gathered by security firm ESET using its LiveGrid telemetry.
The UK has seen a spike in ransomware attacks looking to seize control of targeted machines and lock users out or destroy data if they do not pay a fee.
The rise is attributed to malicious code called JS/Danger.ScriptAttachment which tries to download and install various malware and execute crypto-ransomware, such as Telsacrypt. This aims to encrypt data and demand payment for it to be decrypted.
ESET IT security specialist Ondrej Kubovic explained that the surge in ransomware occurred between 19 and 26 April.
“To reach as many potential victims as possible, attackers are spamming inboxes in various parts of the world. Therefore, users should be very cautious about which messages they open,” he said.
“If an email comes from an unknown sender or its contents are not expected, it should be deleted. Companies should also train employees to report similar incidents to their internal security departments.”
Kubovic advised users to install reliable security software, keep operating systems up to date and back up sensitive data so that it can be recovered in the event of an attack.
Hackers are often opportunistic, so it comes as no great surprise that the use of ransomware is growing. But the attacks are becoming more prolific, sophisticated and clandestine.
The recently detected Dogspectus ransomware can install itself on Android smartphones without users knowing, and the first Mac OS X ransomware was discovered this year that demanded payment in bitcoin.
Ransomware is a particular problem as it can wreak havoc with entire networks of machines and their users and organisations, so much so that the FBI recently requested help from the security sector.
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