U.S. companies and government agencies suffered a record 1,093 data breaches last year, a 40 percent increase from 2015, according to the Identity Theft Resource Center.

Headline-grabbing hacks, with victims ranging from Wendy's Co. to the Democratic National Committee, are increasing despite regulatory scrutiny and more aggressive cybersecurity spending. Worldwide spending on security-related hardware, software and services rose to $73.7 billion in 2016 from $68.2 billion a year earlier, according to researcher IDC. And that number is expected to approach $90 billion in 2018.

"We are extremely confident that breaches are undiscovered and under-reported, and we don't know the full scope," Eva Casey Velasquez, CEO of the Identity Theft Resource Center, said in an interview. "This isn't the worst-case scenario we are looking at; this is the best-case scenario."