Ransomware has turned out to be the most popular form of malware used in cyber attacks, suggests a study.
According to the annual Verizon data breach investigation report, up to 40% of all successful malware-based attacks involved ransomware.
The types of systems compromised were changing too, it found, with criminals trying to hit databases not just PCs.
It also indicated that firms had significant success dealing with some types of cyber attacks.
They had particular success in dealing with attempts to knock web servers offline and spotting phishing emails.
Gabe Bassett, senior information security scientist at Verizon who helped compile the report said "Ransomware breaches doubled last year and could double again this year."
"Once ransomware infects a machine it encrypts data until a payment, usually in the form of a popular cryptocurrency, is made."
Mr Bassett added that ransomware was popular owing to the fact that it allows cyber-thieves quickly cash in on the security mistakes made by firms both large and small.
The research also pointed out that Desktop computers were most likely to be compromised by ransomware, but attackers had started turning their attention to more critical business systems.
"We are seeing more and more databases hit as attackers find these systems online and encrypt them," said Mr Bassett, adding that the numbers of such attacks trebled last year.
He said these were attractive targets because companies were more likely to pay a high ransom to unlock the business-critical data.
Bill Conner, chief executive at security firm SonicWall, said the high-profile WannaCry and NotPetya ransomware attacks in 2017, were behind the growing popularity of the category. And, he added, it was now starting to hit a very "target rich" segment.
"Ransomware is really the first time that medium and small companies have been targeted. But they are least prepared because they have the least money and they cannot go out and hire cyber-experts," he said.
