GHSA-889w-m37p-88m5

### Summary An admin who revokes or downgrades a non-admin user's permissions through pyLoad's own documented `/api/<func>` RPC surface — e.g. `POST /api/set_user_permission` (or its legacy alias `/api/setUserPermission`) — updates the target's database row but never invalidates that user's existing Flask cookie session. The demoted user keeps their pre-revocation `role`/`permission` bits on every subsequent WebUI page load and every subsequent `/api/<func>` call made with that cookie, for up to the default `session_lifetime` of ~31 days, or until they voluntarily log out. No action by the demoted user is required beyond already being logged in at the time of revocation. ### Details The vulnerable method, verbatim, at `src/pyload/core/api/__init__.py:1652-1656`: ``` @legacy("setUserPermission") @post def set_user_permission(self, user: str, permission: int, role: int) -> None: self.pyload.db.set_permission(user, permission) self.pyload.db.set_role(user, role) ``` It carries no `@permission(...)` decorator and its body never calls `clear_all_user_sessions` or any other session-invalidation routine. The **only** call site in the entire codebase that pairs a permission/role change with `clear_all_user_sessions` is the WebUI's `update_users()` route, `src/pyload/webui/app/blueprints/json_blueprint.py:442-444`: ``` api.set_user_permission(name, data["permission"], data["role"]) if was_changed: clear_all_user_sessions(name) ``` A repo-wide grep for `set_user_permission|setUserPermission` returns exactly 3 hits: the `@legacy` alias registration (`core/api/__init__.py:1652`), the method definition itself (`:1654`), and this one call site (`json_blueprint.py:442`). No other caller exists. pyLoad's own public RPC dispatcher reaches `Api.set_user_permission` directly, bypassing `json_blueprint.py` entirely. `src/pyload/webui/app/blueprints/api_blueprint.py:21-26` registers `rpc(func, args="")` on `/api/<func>` and