Schools across the United Kingdom are being encouraged to sign up for a free service developed by cyber experts inside the country’s security and intelligence services that would help protect them from ransomware attacks and other online threats.

Cyberattacks affecting schools can pose a severe risk to children, not only in disrupting their access to education and the other services schools provide, but also by publishing sensitive documents regarding at-risk students in extortion attempts.

On Tuesday, the National Cyber Security Centre (NCSC) — a part of the signals and cyber intelligence agency GCHQ — announced that to help prevent these attacks, it was rolling out its PDNS (Protective Domain Name System) for Schools service nationally.

The PSNS for Schools service is the same technology already used across central government, the emergency services and the Ministry of Defence. It was developed by NCSC and is delivered by Cloudflare and Accenture.

It protects these organizations by preventing computers on their networks from connecting with a list of known malicious domains. This list is built by a range of feeds, including some only accessible to the intelligence services, and can block access to a malicious domain within 30 minutes of that domain being discovered.

The move to protect all schools in the country comes as ransomware incidents disrupting the childcare and education sector have reached record levels, with 131 incidents reported to the data protection regulator last year.

Preliminary figures suggest at least 47 schools suffered ransomware attacks in the first half of this year that involved compromising personal data. Schools in London and West Sussex are among those known to have been attacked, as is a school in Leeds for children with special educational needs.

Ofqual, Britain’s qualifications and examinations regulator, has warned that more than a third of schools experienced a cyber incident during the last academic year, with some incidents taking several weeks to recover from.

Sarah Lyons, the NCSC’s deputy director for economy and society, said: “With a growing range of cyber threats, it has never been more important to protect our educational environments from online threats.

“The PDNS for Schools service offers a crucial layer of protection, helping schools defend against common online threats, at no cost.”

All educational organizations can sign up for PDNS for Schools by asking their DNS provider to register through MyNCSC.