University College London has been hit by a ransomware attack.
Ransomware is a form of malicious software which locks the files on a victim’s computer until they pay a ransom to the cybercriminal.
After a widespread attack targeted UCL, the institution was forced to disconnect large parts of its IT system.
It is not known how similar the malicious software is to the WannaCry ransomware which infected NHS computers in May.
The university’s information services division claimed its virus checkers did not show any suspicious activity or catch the attack.
UCL believes the malware was able to infect its systems through phishing emails – emails which contain malicious links or attachments – which a user was tricked into clicking on.
There are many reasons a virus checker could have failed to catch the phishing emails – including it not being particularly good.
UCL believes it has “currently contained the risk of further infection” but notes that the attack “is still under active investigation”.
“We must continue to be vigilant,” UCL warned its community.
“If you receive email that is unexpected or in any way suspicious then you must not open any attachment or follow any link in the email.
“Doing so may lead to loss of your data and very substantial disruption to the university.”