Unverified Email Change - Email as part of Credential / Unverified Account Recovery Channel Change

The application allows changing the account email address (used as a login identifier and/or password recovery address) without verifying the requester’s authority to make that change (no confirmation to the old email, no authentication step). Because email often functions as a credential or recovery channel, unverified email changes enable attackers to take over accounts by switching the account’s recovery/login address.

Occurence - code: https://github.com/FlowiseAI/Flowise/blob/main/packages/ui/src/views/account/index.jsx#L211

Remote and physical scenarios can be considered.

Later this email is needed as credentials to log in or reset password feature.

POC: Email changed, and notice "Profile updated" message.

Screenshot

Full account takeover (ATO) of affected accounts (loss of confidentiality and integrity of account data). User account recovery mechanisms (password reset flows tied to email) can be bypassed or abused if combined with this issue and the second one which I've reported (similar security issue with the password - part of credentials). (gain persistence)