CVE-2013-5480: Cisco IOS

High severity, CVSS 7.8. EPSS: 1.3% chance of exploitation in the next 30 days.

The DNS-over-TCP implementation in Cisco IOS 12.2 and 15.0 through 15.3, when NAT is used, allows remote attackers to cause a denial of service (device reload) via a crafted IPv4 DNS TCP stream, aka Bug ID CSCuf28733.

Affected products

• Cisco IOS: version 12.2 only; version 15.0 only; version 15.1 only; version 15.2 only; version 15.3 only

Published 2013-09-27. Last modified 2026-06-16.