Medium [CVE-2026-17350] pgAdmin 4: Permission bypass allows authenticated users to access restricted tools

The per-tool permission system (custom roles / role-based tool permissions, introduced in pgAdmin 4 9.3) did not enforce its permission check consistently. In SERVER mode, pgAdmin 4 gates each tool behind a per-tool Flask-Security permission, but the permission decorator (permissions_required) was applied only to a single "front door" route per tool.

Every other backend route and Socket.IO handler in that tool's workflow relied solely on pga_login_required/socket_login_required, which check authentication but not the tool permission.

The reporter verified three cases against a test build: (1) a user without tools_query_tool permission received 403 on the protected sqleditor initialization route, but the same session went on to connect the server, initialize the viewdata backend chain, and retrieve real table row content; (2) a user without tools_grant_wizard received 403 on the protected acl route, but the same session still enumerated grantable objects, generated GRANT SQL, and successfully applied it -- confirmed database-side via has_table_privilege(); (3) a user without tools_schema_diff received 403 on the protected panel route, but the same session initialized schema diff, enumerated and connected databases, and obtained real DDL differences via the compare_database Socket.IO handler.