Cyber Security Bulletin: Phishing Attack Campaigns Target MS Teams Users

A new attack vector has been identified specific to those organizations that use Microsoft Teams for collaboration with internal teams as well as with your customers. The phishing campaign pretends to be an automated message from Microsoft Teams. In reality, the attack aims to steal Office 365 recipients’ login credentials.

Teams is Microsoft’s popular collaboration tool, which has particularly risen in popularity among remote workforces during the pandemic. This particular campaign was sent to between 15,000 to 50,000 Office 365 users with suspicion that additional campaigns will be forthcoming. Because Microsoft Teams is an instant-messaging service, recipients of this notification might be more apt to click on it so that they can respond quickly to whatever message they think they may have missed based on the notification.

The initial phishing email displays the name “There’s new activity in Teams,” making it appear like an automated notification from Microsoft Teams. Within the body of the email, there are three links appearing as ‘Microsoft Teams’, ‘(contact) sent a message in instant messenger’, and ‘Reply in Teams’,” according to researchers. Clicking on any of these leads to a fake website that impersonates the Microsoft login page. The phishing page asks the recipient to enter their email and password.

Further, the phishing landing page also looks convincingly like a Microsoft login page with the start of the URL containing “microsftteams.” If recipients are convinced to input their Microsoft credentials into the page, they are unwittingly handing them over to attackers, who can then use them for an array of malicious purposes – including account takeover. See one sample of the phishing email below.​​​​​​​

In May, a similar convincing campaign that impersonated notifications from Microsoft Teams in order to steal the Office 365 credentials of employees circulated, with two separate attacks that targeted as many as 50,000 different Teams users.

Users are warned to be diligent in reading all invites such as described above and when in doubt, delete the email and not click on any of the display areas.​​​​​​​

Please reach out to us with your concerns or for more information on how to protect yourself and your business.