LinkedIn Alert: Phishing scam uses security update to steal users’ credentials

Symantec said it has observed an increase in phishing emails claiming to be from LinkedIn Support. The body of the email claims that irregular activities have prompted a “compulsory security update” for the recipients’ LinkedIn account. The email goes on to say, “Due to irregular activities your LinkedIn account has been subjected to compulsory security update. LinkedIn may sometimes deny logins in cases where we believe the account could have been compromised. To do this we developed a new secure way that keeps your account safe. We have attached a form to this mail to complete this process. Please, download the form and follow the instructions on your screen.” The attachment is a copy of the real LinkedIn.com website. However, the website’s source has been modified, so if the recipient uses this web page to sign in to their LinkedIn account, their credentials will be sent directly to the attacker.

Curiously, the email uses a lowercase I instead of a capital i when spelling ‘LinkedIn’. The difference in characters is indiscernible to the eye and functions as a way to evade mail filters. However, the most important technique used here is the HTML attachment. This method bypasses browser blacklists that often flag suspicious websites to help prevent users from being phished. LinkedIn users should consider turning on two-step verification, a true ‘security update’ that provides an extra layer of security. With two-step verification enabled, even if a user’s credentials are compromised, an attacker would not be able to login without having access to the user’s mobile phone. To learn more about LinkedIn’s two-step verification, please visit its  help center .