More than two-thirds of business executives are worried their IT systems are open to malicious attacks.
The ThreatTrack Security survey of US companies revealed 69 per cent of senior personnel felt they needed effective vulnerability management against malware attacks, advanced persistent threats (APTs) and other sophisticated cybercrime.
Financial organisations were among the businesses most likely to fear online espionage, with 82 per cent claiming they are anxious about APTs.
Just 50 per cent of firms in the sector said they are aware of targeted malware attacks against their company, while 53 per cent of manufacturing firms said the same.
These still compared well with the overall average, which was 33 per cent.
Around one in five enterprises admitted that not knowing whether an attack is currently taking place is their largest concern.
Loss of proprietary intellectual property and trade secrets to a breach was more important for 36 per cent of businesses than compromising customers' personal information, including credit card data, social security numbers or medical records.
Cyber security remained a concern even for companies that had budgets of over US$1 million (AU$1.08 million) to deal with such threats, with 97 per cent of high-level executives still saying they felt vulnerable to attack.