Google said that up to 1 million Gmail users were victimized by yesterday s Google Docs phishing scam that spread quickly for a short period of time. The messages claimed that someone wanted to share a Google Doc with the victim, and once the Open in Docs button in the email is clicked, the victim is redirected to a legitimate Google OAUTH consent screen. Google says it was able to stop the campaign within approximately one hour. Researchers say the scam was particularly effective because it did not require email spoofing.
Source: https://threatpost.com/1-million-gmail-users-impacted-by-google-docs-phishing-attack/125436/