CVE-2026-89289: Unknown Fast Courier

Medium severity, CVSS 5.3. EPSS: 0.2% chance of exploitation in the next 30 days.

The Fast Courier WordPress plugin through 5.2.3 does not restrict an unauthenticated REST route that writes order fulfillment data, allowing unauthenticated attackers to overwrite the courier status and customer-facing tracking details of any WooCommerce order by supplying its id.

Affected products

• Unknown Fast Courier: up to and including 5.2.3

Published 2026-10-06. Last modified 2026-10-06.