CVE-2024-20303

HIGH
Published Mar 27, 2024 Modified Jul 31, 2025 CWE-459

Description

A vulnerability in the multicast DNS (mDNS) gateway feature of Cisco IOS XE Software for Wireless LAN Controllers (WLCs) could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition. This vulnerability is due to improper management of mDNS client entries. An attacker could exploit this vulnerability by connecting to the wireless network and sending a continuous stream of specific mDNS packets. A successful exploit could allow the attacker to cause the wireless controller to have high CPU utilization, which could lead to access points (APs) losing their connection to the controller and result 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-459 CWE-459

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
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
cisco ios_xe
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-2024-20303? +
A vulnerability in the multicast DNS (mDNS) gateway feature of Cisco IOS XE Software for Wireless LAN Controllers (WLCs) could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition. This vulnerability is due to improper management of mDNS client entries. An attacker could exploit this vulnerability by connecting to the wireless network and sending a continuous stream of specific mDNS packets. A successful exploit could allow the attacker to cause the wireless controller to have high CPU utilization, which could lead to access points (APs) losing their connection to the controller and result in a DoS condition. It has a CVSS v3.1 base score of 7.4 (HIGH).
How severe is CVE-2024-20303? +
CVE-2024-20303 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-2024-20303? +
CVE-2024-20303 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-2024-20303? +
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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