CVE-2003-1398: Cisco IOS

High severity, CVSS 9.3. EPSS: 1.8% chance of exploitation in the next 30 days.

Cisco IOS 12.0 through 12.2, when IP routing is disabled, accepts false ICMP redirect messages, which allows remote attackers to cause a denial of service (network routing modification).

Affected products

• Cisco IOS: version 12.0 only; version 12.0s only; version 12.0st only; version 12.0t only; version 12.1 only; version 12.1e only; …

Published 2003-12-31. Last modified 2026-06-16.