Rejetto HFS 3.0.0 through 3.2.0 returns observably different responses from its login endpoint depending on whether the submitted username exists. A remote unauthenticated attacker can use this to confirm valid account names, including the default admin account, facilitating password-guessing and session-forgery attacks.
Credits
Zach Hanley (@hacks_zach) of Horizon3.ai, in collaboration with Claude and Anthropic Research
