Security researchers from Trustwave found that some users of popular websites including Facebook, Twitter and LinkedIn may have been infected with password-stealing malware. Many of the stolen passwords were a simple series of numbers or even just the word "password". While it's unclear how many accounts in the U.S. were compromised, experts say you should be careful.
"Do not reuse passwords across services. That way, if your Facebook password gets stolen, hackers do not also have access to your bank account," John Miller, Trustwave, said.
Miller said consumers should update anti-virus software and use a strong password that includes upper and lower case letters, numbers and special symbols.