Businesses are being warned about an email scam that encrypts files and demands a ransom to unlock them.
The Business Crime Reduction Centre says the email contains malicious software that aims to trick employees into clicking a link to Dropbox, the online file transfer service.
The user is prompted to download an ‘invoice payment’ or ‘tax return form’ that installs malware.
After the computer is infected it encrypts files and demands a ransom to unlock them.
Fraudsters are using emails designed to look like they are from well-known banks such as HSBC and RBS.
According to PhishMe, an anti-phishing website, the email subject matter always concerns important financial issues, such as invoice payments or tax returns.
BCRC’s cyber security specialist, Mark Connell, said: “Dropbox is being used to host malware as its name provides credibility to the scam emails.
“While many users are suspicious of links in emails, Dropbox is widely used in legitimate business communications.
“Tell-tale signs of a scam include grammatical errors, spelling mistakes and generic greetings such as ‘Dear customer’.”
Dropbox has responded by deleting malware files. However, a risk remains during the window between the scam emails being sent and Dropbox removing the files - meaning businesses should remain vigilant.
Business Crime Reduction Centre, which helps business in the Yorkshire and Humber region cope with cybercrime, is warning people not to click on suspicious links in unsolicited emails, reply or forward the email, or contact the senders.