Graylog2 Server before commit 46a2eeb contains a missing per-entity permission check in the POST /events/definitions/{definitionId}/duplicate endpoint that allows authenticated users to clone any event definition. Attackers with the low-privilege eventdefinitions:create capability can read private event definitions including detection queries, aggregation thresholds, grouping fields, schedules, and notification bindings by duplicating them.
CWE-862