CVE-2025-20340CWE-400denial-of-service

CVE-2025-20340

High · published September 10, 2025

CVSS v3.1
7.4
EPSS
1%
Percentile
50.1
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
7.4 · HIGH
Vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00641 · 50.1th percentile
Weakness
CWE-400 · Uncontrolled Resource Consumption
Published
2025-09-10T20:15Z
References (1)
EPSS history
Timeline
  • 10 SEP 16:06Z
    Cisco IOS XR Address Resolution Protocol Broadcast Storm Vulnerability
    cvelistv5