When UK Defence Secretary John Healey raised concerns about Russian activity near Britain’s undersea infrastructure, he underscored a stark reality: almost all international data flows through subsea cables.

Listen to this article

These hidden networks carry the lifeblood of the modern economy, yet their importance is often overlooked - until they are threatened.

Days earlier, the National Cyber Security Centre (NCSC) had issued a warning that pointed to the same vulnerability from another angle. APT28, a Russian cyber actor, had been exploiting vulnerable routers and hijacking internet traffic. These are not separate issues. While one centres on submarines and cables, and the other on routers and passwords, both are happening on the same network - just at different points.

Britain’s adversaries are probing the digital infrastructure on which its economy and security depend, and the scale of that threat is growing. The NCSC handled 204 nationally significant cyber-attacks in the 12 months to August 2025, up from 89 the year before. Eighteen were classed as highly significant - almost 50 per cent more than the previous year.

The........

© LBC