CVE-2026-105636: Makeplane Plane

Critical severity, CVSS 9.9. EPSS: 0.4% chance of exploitation in the next 30 days.

Plane is an open-source project management tool. Prior to 1.4.0, the webhook delivery task in apps/api/plane/bgtasks/webhook_task.py calls requests.post() without allow_redirects=False and does not validate redirect targets. validate_url() blocks private, loopback, link-local, and reserved addresses in the original webhook URL, but the final URL reached after one or more redirects is not checked. A user who can create a workspace can register a webhook pointing to an attacker-controlled public endpoint that returns a 302 redirect to an internal address. The Plane worker then fetches internal resources, including cloud metadata, and stores the response body in webhook_logs, where the attacker can retrieve it through the workspace webhook-logs API. This issue is fixed in 1.4.0.

Affected products

• Makeplane Plane: before 1.4.0 (fixed in 1.4.0)

Published 2026-10-05. Last modified 2026-10-07.