Discourse's Fail-Open Access Control in Data Explorer Plugin Allows Unauthorized SQL Query Execution

Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, fail-open access control in Data Explorer plugin allows any authenticated user to execute SQL queries that have no explicit group assignments, including built-in system queries. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue. As a workaround, either explicitly set group permissions on each Data Explorer query that doesn't have permissions, or disable discourse-data-explorer plugin.