djust authentication bypass: a login_required / on_mount LiveView mount redirect does not close the WebSocket, allowing an unauthenticated client to dispatch event-handler calls

Summary

djust provides Phoenix LiveView-style reactive server-side rendering for Django with Rust-powered performance. Prior to 1.0.4, LiveViewConsumer.handle_mount sends a `{"type":"navigate","to":...}` frame when login_required, permission_required, or a redirecting on_mount hook denies a LiveView mount, but returns without closing the WebSocket or clearing self.view_instance. A browser follows the redirect, but a raw WebSocket client can ignore it and retain the mounted socket. Because LiveViewConsumer.handle_event does not recheck authentication or authorization, the client can send `{"type":"event",...}` frames that invoke @event_handler methods without an authenticated session, including through handle_live_redirect_mount, enabling unauthorized sensitive reads or mutations. This issue is fixed in version 1.0.4.

Timeline

1. Aug 25, 2026, 4:05 PM UTCCVE published
2. Aug 25, 2026, 5:53 PM UTCCISA SSVC assessment

   Exploitation: poc · Automatable: yes · Technical impact: partial

3. Aug 25, 2026, 5:56 PM UTCRecord last updated

Affected versions

• djust-org djust

  fixed in 1.0.4

• djustPyPI

  fixed in 1.0.4

References 4