Vulnerability identifier: #VU87904

Vulnerability risk: Low

CVSSv3.1: 6.4 [CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2024-20303

CWE-ID: CWE-459

Exploitation vector: Local network

Exploit availability: No

Vulnerable software:
Cisco IOS XE
Operating systems & Components / Operating system
Catalyst 9800-CL Wireless Controllers for Cloud
Hardware solutions / Routers & switches, VoIP, GSM, etc
Catalyst 9800 Embedded Wireless Controller
Hardware solutions / Routers & switches, VoIP, GSM, etc
Catalyst 9800 Series Wireless Controllers
Hardware solutions / Routers & switches, VoIP, GSM, etc
Embedded Wireless Controller on Catalyst Access Points
Hardware solutions / Routers & switches, VoIP, GSM, etc

Vendor: Cisco Systems, Inc

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to incomplete cleanup in the multicast DNS (mDNS) gateway feature. A remote attacker on the local network can cause the wireless controller to have high CPU utilization, leading to denial of service condition.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Cisco IOS XE: 17.6 - 17.9.3a

Catalyst 9800-CL Wireless Controllers for Cloud: All versions

Catalyst 9800 Embedded Wireless Controller: All versions

Catalyst 9800 Series Wireless Controllers: All versions

Embedded Wireless Controller on Catalyst Access Points: All versions

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External links
http://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-wlc-mdns-dos-4hv6pBGf

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.