The latest survey of the attack landscape reveals that one in severn large organisations was hacked last year and the average firm is facing an attack a week with small businesses also being targeted on a monthly basis.
The average cost of a large firm's worst breach is £110k-£250k and £15k-£30k for a small business.
Against the backdrop of the InfoSec show in London the 2012 Information Security Breaches Survey, carried out by PwC in conjunction with Infosecurity Europe with the support of the Department for Business, Innovation and Skills, was unveiled with a warning that not enough is being done to protect UK firms from hackers.
Despite the rising threats a significant portion 20% spend just 1% of their IT budgets on security even given the rising tide of issues around cloud, bring your own device and the need to move to next generation firewalls. Chris Potter, PwC information security partner, said that the attacks on UK businesses were relentless and as a result the number of breaches continued to rise.
"The number of security breaches large organisations are experiencing has rocketed and as a result, the cost to UK plc of security breaches is running into billions every year. Since most businesses now share data with their business partners across the supply chain, these numbers are startling and make uncomfortable reading for business leaders," he said.
"Large organisations are more visible to attackers, which increases the likelihood of an attack on their IT systems. They also have more staff and more staff-related breaches which may explain why small businesses report fewer breaches than larger ones. However, it is also true that small businesses tend to have less mature controls, and so may not detect the more sophisticated attacks," he added.
The Universities and Science Minister David Willetts, whose responsibilities include cyber security issues, said that firms had to do more.
"The survey demonstrates why the Government is right to be investing £650m to improve cyber security and make the UK one of the safest places to do business in cyberspace. We will use the findings to help design a new annual survey of cyber security breaches beginning next year."