CVE-1999-0843: Cisco Router

Medium severity, CVSS 5.0. EPSS: 1.4% chance of exploitation in the next 30 days.

Denial of service in Cisco routers running NAT via a PORT command from an FTP client to a Telnet port.

Affected products

• Cisco Router: any version

Published 1999-11-04. Last modified 2026-06-16.