Participants in a survey of companies involved in supplying and maintaining critical infrastructure components such as energy and telecom services reported a sharp increase in the number of attacks against systems vital for operations.
More than three-quarters of respondents indicated the frequency of attacks was increasing, while more than half say they have been specifically targeted by hackers.
Companies reported an average of ten attacks over the past five years, and nearly half of those surveyed expect to be subject to another attack in the next twelve months.
"To counter such threats, it is necessary to implement comprehensive solutions for protecting networks, which include safety features, storage solutions and data backup, as well as the process of user identification and access control systems to the network," stated director of Symantec's technical solutions Nikolai Pochinok.
One third of the companies queried indicate they are equipped to counter future attacks, and an equal number believe they are not prepared to defend their systems.
The survey reinforces what many information security experts have been saying for a number of years: vulnerabilities in SCADA and critical infrastructure networks represent a serious national security threat.