Email Subscribers & Newsletters < 5.9.11 - Unauthenticated Action Scheduler Task Execution

Description

The plugin is vulnerable to Missing Authorization due to the plugin not properly verifying that a user is authorized to perform an action in the `run_action_scheduler_task` function. This makes it possible for unauthenticated attackers to execute scheduled actions early or repeatedly by guessing action IDs, potentially triggering email sends, maintenance tasks, or other privileged operations, causing unexpected state changes and resource usage.