Destroy our cyber enemies, say MPs He revealed that one attack cost a London business £800 million. In its annual report, the ISC said defending against cyber attacks must be a priority for Britain but "there are also opportunities for our intelligence and security agencies and military which should be exploited in the interests of UK national security." It said those include the "active defence" of interfering with the systems of people trying to hack into British networks. GCHQ, MI5 and MI6 should also be involved in "exploitation" by accessing networks of targets to obtain intelligence and "disruption," which involves hampering their activities or capabilities without detection. The report highlighted the Stuxnet virus, which did not involve British agencies but is believed to have specifically disrupted the Iranian nuclear enrichment programme. However, the report raised concerns that "much of the work to protect UK interests in cyberspace is still at an early stage." It said: "Twenty months into the National Cyber Security Programme, there appears to have been some progress on developing cyber capabilities. However, cyber security is a fast-paced field and delays in developing our capabilities give our enemies the advantage. In a public speech last month, Mr Evans said weak points in state and commercial systems were being "exploited" by thousands of hackers and that the danger had increased because the internet was connected to most aspects of modern daily life. The National Security Strategy ranks the threat of cyber attacks alongside that of terrorism. It is widely accepted that Russia and China sponsor many cyber incidents. The report said GCHQ believes 80 per cent of cyber attacks are preventable through simple means, such as using appropriate security software and strong passwords.