Hackers have used ransomware to encrypt files at a school, causing it to lose some students' GCSE coursework.
The Sir John Colfox Academy in Bridport, Dorset, said a member of staff mistakenly opened an email containing a virus.
The email claimed to be from a colleague at another Dorset school and infected the computer network. Coursework from one subject submitted by Year 11 students, which was saved on the school' system, has been lost.
Head teacher David Herbert said: "We are liaising with the relevant exam boards about this specific issue." Mr Herbert added a police expert "has advised us that it is very unlikely that any school information has left the building and we are not compromised in that way".
"Personal data relating to staff, students and parents is not held on this system and is secure," he said. The BBC website has the analysis. Attacks using phishing emails with infected attachments can be extremely expensive in downtime. Stepping employees through new-school security awareness training is a great way to manage the ongoing problem of social engineering.