CVE-2018-4002: Cujo Smart Firewall Firmware

High severity, CVSS 7.5. EPSS: 1.6% chance of exploitation in the next 30 days.

An exploitable denial-of-service vulnerability exists in the mdnscap binary of the CUJO Smart Firewall running firmware 7003. When parsing labels in mDNS packets, the firewall unsafely handles label compression pointers, leading to an uncontrolled recursion that eventually exhausts the stack, crashing the mdnscap process. An unauthenticated attacker can send an mDNS message to trigger this vulnerability.

Affected products

• Cujo Smart Firewall Firmware: version 7003 only

Published 2019-10-31. Last modified 2026-06-17.