Yesterday afternoon many users of Google products received an email, in some cases from a trusted contact, that asked them to open a Google Doc. When the user attempted to open the Google Doc link, they received a message asking for permission to access their Google account. Those who gave this permission unknowingly gave their account information to a malicious third-party.
Google blocked this attack within a few hours, but please be aware that a similar attack could happen again, and not just with Google account permissions. Facebook and LinkedIn accounts are also frequently used to access other websites, and these could be used for similar attacks in the future.