CVE-2006-4776: Cisco IOS

High severity, CVSS 7.5. EPSS: 7.8% chance of exploitation in the next 30 days.

Heap-based buffer overflow in the VLAN Trunking Protocol (VTP) feature in Cisco IOS 12.1(19) allows remote attackers to execute arbitrary code via a long VLAN name in a VTP type 2 summary advertisement.

Affected products

• Cisco IOS: version 12.1(19) only

Published 2006-09-14. Last modified 2026-06-16.