Forty-seven percent of the 229 U.S.-based companies surveyed said their internal networks were compromised by worms last year. Twenty-three percent said their networks were breached by a credentialed user.
The survey indicated some major internal vulnerabilities: Forty-six percent reported active user accounts that belong to former employees while 31 percent reported rogue wireless access points.
The survey was conducted by Mazu Networks by the Enterprise Strategy Group, a market-research firm. The survey queried security and IT professionals at companies with more than 1,000 employees.