CVE-2011-2395: Cisco IOS

Medium severity, CVSS 5.0. EPSS: 2.3% chance of exploitation in the next 30 days.

The Neighbor Discovery (ND) protocol implementation in Cisco IOS on unspecified switches allows remote attackers to bypass the Router Advertisement Guarding functionality via a fragmented IPv6 packet in which the Router Advertisement (RA) message is contained in the second fragment, as demonstrated by (1) a packet in which the first fragment contains a long Destination Options extension header or (2) a packet in which the first fragment contains an ICMPv6 Echo Request message.

Affected products

• Cisco IOS: version 4.1 only; version 4.1.1 only; version 4.1.2 only; version 8.2 only; version 8.3 only; version 9.0 only; …

Published 2011-06-09. Last modified 2026-06-16.