Microsoft Teams Cookie Decryption Attack
A critical Microsoft Teams cookie vulnerability, explains that security researchers discovered a flaw in how Teams encrypts authentication cookies using the weaker Data Protection API (DPAPI), rather than more secure system-level protections. This weakness allows attackers with standard user privileges to extract and decrypt sensitive session cookies using a specialized tool called teams-cookies-bof, which bypasses file locks by operating within the Teams application process. Successful exploitation grants threat actors the ability to impersonate users, read communications, and potentially expand access across the Microsoft 365 ecosystem. Finally, the text provides immediate defensive measures and long-term security recommendations from the fictional cybersecurity firm Technijian, which offers services like EDR implementation and penetration testing to mitigate this high-priority threat.
