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CVE-2025-20340 Detail

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.


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-arp-storm-EjUU55yM Cisco Systems, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-400 Uncontrolled Resource Consumption Cisco Systems, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-20340
NVD Published Date:
09/10/2025
NVD Last Modified:
09/11/2025
Source:
Cisco Systems, Inc.