Executive brief
OpenClaw is a Slack monitoring tool that uses sender policies to control which users' events are processed. A flaw in how reaction and pin events are handled allows events from unauthorized senders to pass through policy checks and be added to the system, potentially exposing unwanted context signals from users who should be blocked. This could enable unauthorized monitoring or manipulation of Slack activity.
Technical details
OpenClaw's Slack monitor failed to consistently apply sender-policy authorization checks to reaction_* and pin_* non-message events before processing them. The vulnerability is rooted in missing authorization enforcement in the event handlers for these event types (CWE-863: Incorrect Authorization). An authenticated user could trigger reaction or pin events that would be ingested into the system-event context despite sender policies that should deny them. The fix routes these handlers through a shared authorizeSlackSystemEventSender function that enforces DM policies, channel-user allowlists, and channel-level allow checks. This is patched in version 2026.2.25.
Affected products
- OpenClaw OpenClaw <= 2026.2.24
Timeline
- 2026-02-26: disclosed
- 2026-02-26: patched: Patched in version 2026.2.25
- 2026-03-03: advisory