CVE-2025-20140

HIGH
Published May 7, 2025 Modified Jul 31, 2025 CWE-789

Description

A vulnerability in the Wireless Network Control daemon (wncd) of Cisco IOS XE Software for Wireless LAN Controllers (WLCs) could allow an unauthenticated, adjacent wireless attacker to cause a denial of service (DoS) condition. This vulnerability is due to improper memory management. An attacker could exploit this vulnerability by sending a series of IPv6 network requests from an associated wireless IPv6 client to an affected device. To associate a client to a device, an attacker may first need to authenticate to the network, or associate freely in the case of a configured open network. A successful exploit could allow the attacker to cause the wncd process to consume available memory and eventually cause the device to stop responding, resulting in a DoS condition.

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CVSS v3.1 Score

7.4
HIGH
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Weakness Type (CWE)

CWE-789 CWE-789

Affected Products

Vendor Product
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
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cisco ios_xe
cisco catalyst_9800-cl_wireless_controllers_for_cloud
cisco catalyst_9105axi
cisco catalyst_9115axe
cisco catalyst_9115axi
cisco catalyst_9117axi
cisco catalyst_9120axe
cisco catalyst_9120axi
cisco catalyst_9120axp
cisco catalyst_9130axe
cisco catalyst_9130axi
cisco catalyst_9800-40
cisco catalyst_9800-80
cisco catalyst_9800-l
cisco catalyst_cw9800h1
cisco catalyst_cw9800h2
cisco catalyst_cw9800m

References

Frequently Asked Questions

What is CVE-2025-20140? +
A vulnerability in the Wireless Network Control daemon (wncd) of Cisco IOS XE Software for Wireless LAN Controllers (WLCs) could allow an unauthenticated, adjacent wireless attacker to cause a denial of service (DoS) condition. This vulnerability is due to improper memory management. An attacker could exploit this vulnerability by sending a series of IPv6 network requests from an associated wireless IPv6 client to an affected device. To associate a client to a device, an attacker may first need to authenticate to the network, or associate freely in the case of a configured open network. A successful exploit could allow the attacker to cause the wncd process to consume available memory and eventually cause the device to stop responding, resulting in a DoS condition. It has a CVSS v3.1 base score of 7.4 (HIGH).
How severe is CVE-2025-20140? +
CVE-2025-20140 has a CVSS v3.1 score of 7.4 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.
What products are affected by CVE-2025-20140? +
CVE-2025-20140 affects products from cisco, specifically: catalyst_9105axi, catalyst_9115axe, catalyst_9115axi, catalyst_9117axi, catalyst_9120axe, catalyst_9120axi, catalyst_9120axp, catalyst_9130axe, catalyst_9130axi, catalyst_9800-40, catalyst_9800-80, catalyst_9800-cl_wireless_controllers_for_cloud, catalyst_9800-l, catalyst_cw9800h1, catalyst_cw9800h2, catalyst_cw9800m, ios_xe. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2025-20140? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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