UK Reports 50% Rise in 'Highly Significant' Cyberattack Incidents Affecting Critical Sectors

Britain is facing a sharp rise in major cyber-attacks, with the number of 'highly significant' incidents up 50% from last year, according to the head of the National Cyber Security Centre (NCSC).

The attacks, which have disrupted major firms including Jaguar Land Rover, Marks & Spencer and the Co-op, highlight growing vulnerabilities across the UK's critical sectors and supply chains.

Cyber Threats Reach Record Levels

Richard Horne, the recently appointed chief executive of the NCSC, issued the warning on Tuesday at the agency's annual review in London.

Horne, who previously led cybersecurity operations at PwC, cautioned that cybercrime is no longer a niche risk but a national challenge requiring leadership from both government and industry.

'Every leader, whether you're one person at your kitchen table or the boss of thousands of people, you must have a plan to defend against criminal cyberattacks,' Horne was quoted by Reuters as saying.

'If your IT infrastructure was crippled tomorrow and all your screens went blank, could you run your payroll systems, keep your machinery working, or stock your shelves? If the answer is no, or more likely "don't know", act now.'

The NCSC — part of Britain's GCHQ intelligence agency — said it had assisted with 429 cyber incidents in the 12 months to August 2025, roughly half of which were classed as "nationally significant". Of those, 18 were deemed "highly significant", meaning they had a serious impact on central government, essential services, or large sections of the UK economy.

High-Profile Attacks Cripple Businesses

In recent months, a series of cyberattacks has disrupted household names and exposed weaknesses in corporate security infrastructure.

Jaguar Land Rover (JLR), owned by Tata Motors, was forced to suspend production for nearly six weeks after a major ransomware incident this summer.

Analysts estimated the shutdown cost the luxury carmaker roughly £50 million per week. The British government stepped in late September with a £1.5 billion loan guarantee to help JLR stabilise operations and support its suppliers.

Retailers Marks & Spencer and the Co-op were also hit by network disruptions that temporarily affected their online and in-store operations.

Although services were restored, the incidents underscored the potential ripple effects of cyberattacks across supply chains, particularly for smaller firms that depend on larger partners for contracts and payments.

Government Urges Firms to Act

The Department for Science, Innovation and Technology (DSIT) confirmed that ministers have written to the UK's 350 largest listed companies on the FTSE Index, urging them to take cyber resilience seriously and treat it as a board-level priority.

'Cybersecurity is no longer the responsibility of IT departments alone,' said a DSIT spokesperson. 'It must be a central element of risk management for any business operating in today's digital economy.'

The NCSC's report showed a more than doubling of serious cyber incidents, from 89 last year to 204 in 2025, within the agency's top three severity categories.

Officials attributed the surge to a combination of increased criminal sophistication, state-sponsored hacking, and the continued targeting of third-party suppliers — often the weakest link in a company's digital defences.

Rising Threat to Critical Infrastructure

The report comes amid growing concern about the UK's ability to protect critical national infrastructure such as energy grids, transport systems, and healthcare networks.

Analysts warn that ransomware gangs and hostile states are increasingly targeting such sectors for disruption and leverage.

Cyber experts have also pointed to the danger of cascading failures — where attacks on a single supplier can paralyse multiple businesses at once.

This phenomenon was starkly illustrated by the attack on JLR, which temporarily halted production at dozens of subcontractor facilities.

'These aren't isolated incidents,' said cybersecurity researcher Emily Carter of King's College London. 'We're seeing systemic risks — where one compromised supplier can trigger economic damage on a national scale.'

A Call for Preparedness

Horne's message to businesses is expected to be unequivocal: cyberattacks are inevitable, but the degree of damage depends on preparation.

'The UK cannot eliminate cyber risk,but it can dramatically reduce its impact by planning ahead, sharing information, and investing in resilience before it's too late,' Horne told Reuters.

The NCSC plans to expand support for small and medium-sized enterprises, which remain disproportionately vulnerable to ransomware and phishing attacks. It is also developing new frameworks for "cyber incident rehearsal" to ensure companies know how to respond when systems go dark.

As the number and complexity of attacks continue to rise, experts agree that cybersecurity is now as essential to business continuity as finance or compliance.

The message from government and industry alike is clear — in an era of digital warfare, cyber resilience has become a cornerstone of national security.