The bill, which passed by a 48-16 vote, is H.R. 3997 -- otherwise known as the Financial Data Protection Act of 2005. It is designed to give financial services companies a national standard for securing sensitive personal information and notifying consumers in the event of a data breach.

Outraged opponents of the bill say that H.R. 3997 would gut stronger state laws already in place and would give companies far too much leeway when it comes to disclosing breaches involving the compromise of sensitive data.

Thursday's passage of the bill "is a really devastating blow for consumers," said Susanna Montezemolo, policy analyst at advocacy group Consumers Union in Washington. "But it's not become law yet," she said.

Ed Mierzwinski, consumer program director of the U.S. Public Interest Research Group (U.S. PIRG) in Washington, called the bill "easily the worst data-breach bill ever."

In a letter addressed to members of the House Financial Services Committee, Mierzwinski and representatives from nine other consumer and privacy groups slammed the proposed bill, claiming that consumers "would be worse off under this bill than if nothing passed."