Bank of America Corp still doesn't know exactly what damaging documents Wikileaks could have about it, the largest U.S. bank's chief information officer said on Thursday.

We don't know what it is, Bank of America's Marc Gordon said during a panel discussion about cyberterrorism moderated by Reuters Editor-in-Chief Stephen Adler on Thursday evening.

Gordon added that the bank has done the diligence we think we need to do to protect itself.

Wikileaks founder Julian Assange has hinted that his website has information that will hurt the reputation of Bank of America. Last year, he said it would be released early in 2011, but the site has yet to publish such data.

The bank and its biggest competitors are facing more immediate threats to their data security. Citigroup Inc, the third-largest U.S. bank by assets, this week said that over 360,000 of its credit card customers' accounts were accessed in a data breach in May that the bank first disclosed last week.

That attack and one last week at the International Monetary Fund have highlighted the new, direct threats that financial institutions are increasingly vulnerable to.

There are points of vulnerability, former National Security Agency director Mike McConnell told the panel. He singled out clearinghouses as probably the biggest point of vulnerability for the banking system.

Even if the banks are able to prevent the majority of cyberattacks, those that occur can do real damage, especially to public confidence in the financial system, the panelists said.

If people aren't confident in banking online ... it's something we have to worry about, said Frank Cilluffo, associate vice president at George Washington University and director of the Homeland Security Policy Institute.

It's not a black swan we can discount, he added.

(Reporting by Maria Aspan; Editing by Gary Hill)