How to fix CVE-2025-20340?

Within 30 days: Identify all affected systems and apply vendor patches as part of regular patch cycle. Monitor vendor channels for patch availability.

Is Apple affected by CVE-2025-20340?

CVE-2025-20340 presents moderate security risk, a resource exhaustion vulnerability rated CVSS 7.4. Exploitation could cause service disruption or denial of service, impacting availability for legitimate users.

CVE-2025-20340

HIGH

2025-09-10 [email protected]

7.4

CVSS 3.1

CVSS Vector

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Attack Vector

Adjacent

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Changed

Confidentiality

None

Integrity

None

Availability

High

Lifecycle Timeline

Analysis Generated

Mar 28, 2026 - 19:11 vuln.today

CVE Published

Sep 10, 2025 - 16:15 nvd

HIGH 7.4

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.

Analysis

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. Rated high severity (CVSS 7.4), this vulnerability is no authentication required, low attack complexity. No vendor patch available.

Technical Context

This vulnerability is classified as Uncontrolled Resource Consumption (CWE-400), which allows attackers to cause denial of service by exhausting system resources. 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.

Affected Products

See vendor advisory for affected versions.

Remediation

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Implement rate limiting, set resource quotas, validate input sizes, use timeouts.

Priority Score

Low Medium High Critical

KEV: 0

EPSS: +0.0

CVSS: +37

POC: 0

CVE-2025-20340 vulnerability details – vuln.today

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CVE-2025-20340

CVSS Vector

Lifecycle Timeline

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Description

Analysis

Technical Context

Affected Products

Remediation

Priority Score

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CVE-2025-20340

CVSS Vector

Lifecycle Timeline

Tags

Description

Analysis

Technical Context

Affected Products

Remediation

Priority Score

Share

External POC / Exploit Code