CVE-2025-20191: Multiple Cisco Products Denial of Service Vulnerability

Published May 7, 2025
·
Updated

A vulnerability in the Switch Integrated Security Features (SISF) of Cisco IOS Software, Cisco IOS XE Software, Cisco NX-OS Software, and Cisco Wireless LAN Controller (WLC) AireOS Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to the incorrect handling of DHCPv6 packets. An attacker could exploit this vulnerability by sending a crafted DHCPv6 packet to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

Affected Software

4 affected components
Cisco IOS software
Cisco IOS XE Software
Cisco NX-OS Software
Cisco Wireless LAN Controller (WLC) AireOS Software

Event History

May 7, 2025
CVE Published
via MITRE·05:18 PM
Data Sourced
via MITRE·05:18 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·06:15 PM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is the severity of CVE-2025-20191?

The severity of CVE-2025-20191 is high, as it can allow an unauthenticated attacker to cause a denial of service.

2

How do I fix CVE-2025-20191?

To fix CVE-2025-20191, update the affected Cisco software to the latest version provided by Cisco.

3

Which Cisco software is affected by CVE-2025-20191?

CVE-2025-20191 affects Cisco IOS Software, Cisco IOS XE Software, Cisco NX-OS Software, and Cisco Wireless LAN Controller AireOS Software.

4

What impact does CVE-2025-20191 have on network devices?

CVE-2025-20191 can lead to a denial of service condition, potentially disrupting network operations.

5

Is there a workaround to mitigate CVE-2025-20191?

Currently, the best mitigation for CVE-2025-20191 is to apply available software updates from Cisco.

Contact

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