CVE-2013-5469: Cisco IOS

High severity, CVSS 7.1. EPSS: 2.4% chance of exploitation in the next 30 days.

The TCP implementation in Cisco IOS does not properly implement the transitions from the ESTABLISHED state to the CLOSED state, which allows remote attackers to cause a denial of service (flood of ACK packets) via a crafted series of ACK and FIN packets, aka Bug ID CSCtz14399.

Affected products

• Cisco IOS: affected versions not specified

Published 2013-08-30. Last modified 2026-06-16.