STEALING MICROSOFT TEAMS ACCESS TOKENS IN 2025

Summary from the TLDR InfoSec newsletter

Microsoft Teams stores its auth_cookie in a DPAPI-encrypted value in the Cookie database of the embedded Chromium browser used by Teams. The key used to encrypt the cookie can be retrieved from the Local State file in the Teams cache and used in conjunction with the nonce to decrypt the auth_cookie using AES-256-GCM. This auth_cookie can then be used with GraphSpy to retrieve and send messages on Teams.