A widely distributed scam email that quoted people's postal addresses links to a dangerous form of ransomware, according to a security researcher. Mr Brandt discovered that the emails linked to ransomware called Maktub. The malware encrypts victims' files and demands a ransom be paid before they can be unlocked.

The phishing emails told recipients they owed hundreds of pounds to UK businesses and that they could print an invoice by clicking on a link - but that leads to malware, as Mr Brandt explained. One of the emails was received by You and Yours reporter Shari Vahl.