CVE-2025-20340

Cisco IOS XR Address Resolution Protocol Broadcast Storm Vulnerability

Severity
High 7.4
CVSS 3.1
Exploited
Not listed
EPSS
0.006
44.8th percentile
Discovered by
Third party
Published by the vendor
Published
Sep 10, 2025
Assigned by cisco

Description

A vulnerability in the Address Resolution Protocol (ARP) implementation of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to trigger a broadcast storm, leading to a denial of service (DoS) condition on an affected device.  This vulnerability is due to how Cisco IOS XR Software processes a high, sustained rate of ARP traffic hitting the management interface. Under certain conditions, an attacker could exploit this vulnerability by sending an excessive amount of traffic to the management interface of an affected device, overwhelming its ARP processing capabilities. A successful exploit could result in degraded device performance, loss of management connectivity, and complete unresponsiveness of the system, leading to a DoS condition.

Weakness: CWE-400

Affected products

Vendor Product Category Matched by
Cisco Cisco IOS XR Software Routing & Switching cna-assigner
Vendor-reported affected versions (1)
  • Cisco · Cisco IOS XR Software