CVE-2020-3359 : Exploit Details and Defense Strategies

A vulnerability in the multicast DNS (mDNS) feature of Cisco IOS XE Software for Cisco Catalyst 9800 Series Wireless Controllers could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition due to improper validation of mDNS packets.

Understanding CVE-2020-3359

This CVE involves a vulnerability in Cisco IOS XE Software for Catalyst 9800 Series Wireless Controllers that could lead to a DoS attack.

What is CVE-2020-3359?

The vulnerability in the multicast DNS (mDNS) feature of Cisco IOS XE Software for Cisco Catalyst 9800 Series Wireless Controllers allows remote attackers to trigger a DoS condition by sending crafted mDNS packets.

The Impact of CVE-2020-3359

The vulnerability has a CVSS base score of 8.6 (High severity) with a high impact on availability. Successful exploitation could lead to device reloads and subsequent DoS conditions.

Technical Details of CVE-2020-3359

This section provides more technical insights into the vulnerability.

Vulnerability Description

The vulnerability arises from improper validation of mDNS packets in Cisco IOS XE Software for Catalyst 9800 Series Wireless Controllers.

Affected Systems and Versions

Product: Cisco IOS XE Software
Vendor: Cisco
Versions: Not applicable (n/a)

Exploitation Mechanism

Attackers can exploit this vulnerability by sending a specifically crafted mDNS packet to the targeted device, causing it to reload and resulting in a DoS condition.

Mitigation and Prevention

To address CVE-2020-3359, follow these mitigation strategies:

Immediate Steps to Take

Apply vendor patches and updates promptly.
Implement network segmentation to limit exposure.
Monitor network traffic for any suspicious mDNS packets.

Long-Term Security Practices

Regularly update and patch all software and firmware.
Conduct security assessments and penetration testing.
Stay informed about security advisories from vendors.

Patching and Updates

Cisco has released patches to address this vulnerability. Ensure timely application of these patches to mitigate the risk of exploitation.