Microsoft users are facing a new wave of security threats, including spam fatigue tactics employed by the notorious Black Basta hacking group. Researchers have analyzed the latest attack campaign and found that hackers are using email flooding followed by Teams chat impersonation to steal account credentials.
The attack chain involves creating a new Microsoft 365 tenant posing as a legitimate support organization, flooding the target’s inbox with benign spam emails, and initiating a one-on-one chat session in Microsoft Teams to offer assistance. The victim is then persuaded to provide access to their account using a remote management tool, allowing attackers to disable security controls, deploy malware, and exfiltrate sensitive information.
To mitigate this attack, experts recommend disabling Teams communication from external users or only allowing specific domains to communicate with the organization. Additionally, setting up anti-spam policies can prevent email inboxes from being flooded with spam emails. Microsoft has been approached for a statement on the matter, but no official response is available at this time.
As security threats continue to evolve, it’s essential for Microsoft users to be aware of these tactics and take necessary precautions to protect their accounts.
Source: https://www.forbes.com/sites/daveywinder/2025/01/20/new-email-warning-hackers-target-microsoft-users-with-fatigue-attack