CVE-2021-1439

Cisco Aironet Access Points FlexConnect Multicast DNS Denial of Service Vulnerability

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.

Category

7.4
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.11%
Vendor Advisory cisco.com
Affected: Cisco Cisco Aironet Access Point Software (IOS XE Controller)
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-1439?
CVE-2021-1439 has been scored as a high severity vulnerability.
How to fix CVE-2021-1439?
To fix CVE-2021-1439, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-1439 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-1439 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-1439?
CVE-2021-1439 affects Cisco Cisco Aironet Access Point Software (IOS XE Controller).
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