It would be easy to think that once someone has logged in successfully to Facebook—and not a phishing site—that the security threat is largely gone. However, that’s not quite the case, as we’ve seen before.
Earlier this week, however, Trend Micro researcher Rik Ferguson found at least two—if not more—malicious applications on Facebook. (These were the Posts and Stream applications.) They were used for a phishing attack that sent users to a known phishing domain, with a page claiming that users need to enter their login credentials to use the application. The messages appear as notifications in a target user’s legitimate Facebook profile.
After entering the credentials, users would then be redirected to Facebook itself.
While Trend Micro has informed Facebook of these findings, users should still exercise caution when entering login credentials. They should be doubly sure that these are being entered into legitimate sites, and not carefully crafted phishing sites. The particular site involved in this phishing attack is already blocked by the Smart Protection Network.
Source: TrendLabs Malware Blog