CVE-2024-20318: Cisco IOS XR Software

High severity, CVSS 7.4. EPSS: 0.3% chance of exploitation in the next 30 days.

A vulnerability in the Layer 2 Ethernet services of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause the line card network processor to reset, resulting in a denial of service (DoS) condition. This vulnerability is due to the incorrect handling of specific Ethernet frames that are received on line cards that have the Layer 2 services feature enabled. An attacker could exploit this vulnerability by sending specific Ethernet frames through an affected device. A successful exploit could allow the attacker to cause the ingress interface network processor to reset, resulting in a loss of traffic over the interfaces that are supported by the network processor. Multiple resets of the network processor would cause the line card to reset, resulting in a DoS condition.

Affected products

• Cisco Cisco IOS XR Software: version 6.5.2 only; version 6.5.3 only; version 6.6.2 only; version 6.6.3 only; version 6.6.25 only; version 7.0.1 only; …

Published 2024-03-13. Last modified 2026-06-17.