CVE-2021-1439 Cisco Aironet Access Points FlexConnect Multicast DNS Denial of Service Vulnerability
An adjacent attacker can cause a denial of service on Cisco Aironet Access Points by sending crafted mDNS packets, requiring FlexConnect local switching or mDNS VLAN configuration.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2021-1439?
CVE-2021-1439 is a high-severity denial of service vulnerability in Cisco Aironet Access Point Software (IOS XE Controller), published on 24 Mar 2021. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
A vulnerability in the multicast DNS (mDNS) gateway feature of Cisco Aironet Series Access Points Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient input validation of incoming mDNS traffic. An attacker could exploit this vulnerability by sending a crafted mDNS packet to an affected device through a wireless network that is configured in FlexConnect local switching mode or through a wired network on a configured mDNS VLAN. A successful exploit could allow the attacker to cause the access point (AP) to reboot, resulting in a DoS condition.
Weakness: CWE-120
Which versions are affected by CVE-2021-1439?
It affects 2 products.
Products include Cisco Aironet Access Point Software, Cisco Catalyst 9800 Firmware.
How do I fix CVE-2021-1439?
No fix has been published for CVE-2021-1439 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2021-1439 being exploited?
There is no known exploitation of CVE-2021-1439 in the wild and no public exploit code.
Other vulnerabilities in Cisco Aironet Access Point Software (IOS XE Controller)
- CVE-2017-3831 Auth bypass in Cisco Mobility Express 1800 Access Point Series
- CVE-2022-20622 Cisco Embedded Wireless Controller with Catalyst Access Points IP Flood Denial of Service Vulnerability
- CVE-2018-0234 Denial of service in Cisco Aironet 1810, 1830, and 1850 Series Access Points
- CVE-2016-1419 Denial of service in n/a
- CVE-2016-6362 Privilege escalation in n/a
Sources
Also known as GHSA-2p9c-p5jq-7j4g.