CVE-2008-3809: Cisco IOS

High severity, CVSS 7.1. EPSS: 2.8% chance of exploitation in the next 30 days.

Cisco IOS 12.0 through 12.4 on Gigabit Switch Router (GSR) devices (aka 12000 Series routers) allows remote attackers to cause a denial of service (device crash) via a malformed Protocol Independent Multicast (PIM) packet.

Affected products

• Cisco IOS: version 12.0 only; version 12.0da only; version 12.0db only; version 12.0dc only; version 12.0sc only; version 12.0sl only; …

Published 2008-09-26. Last modified 2026-06-16.