CVE-2026-86174: Makeplane Plane

Medium severity, CVSS 4.3. EPSS: 0.3% chance of exploitation in the next 30 days.

Plane through 1.4.2 fails to validate that issues belong to the deploy board's project in the public comment endpoint. Authenticated attackers can post comments to arbitrary issues across workspaces by supplying an issue_id parameter to the public deploy-board comment endpoint.

Affected products

• Makeplane Plane: up to and including 1.4.2

Published 2026-09-05. Last modified 2026-09-16.