Microsoft Teams stores authentication tokens in unencrypted plaintext mode, allowing attackers to potentially control communications within an organization, according to the security firm Vectra. The ...

Attackers who gain initial access to a victim's network now have another method of expanding their reach: using access tokens from other Microsoft Teams users to impersonate those employees and ...

Microsoft’s Teams client stores users’ authentication tokens in an unprotected text format, potentially allowing attackers with local access to post messages and move laterally through an organization ...

This is a known issue with OAuth and is how basically any electron app works. The tl;dr is if you're able to steal files "as the user" it's already game over. This is no different than stealing ...