CVE-2019-1920 : What You Need to Know

Cisco IOS Access Points Software 802.11r Fast Transition Denial of Service Vulnerability

Understanding CVE-2019-1920

This CVE involves a weakness in the implementation of 802.11r Fast Transition in Cisco IOS Access Points Software, potentially allowing nearby unauthenticated attackers to trigger a denial of service (DoS) situation.

What is CVE-2019-1920?

The vulnerability arises due to inadequate error handling in client authentication requests for Fast Transition on a specific interface, enabling attackers to disrupt the affected interface by sending crafted authentication request traffic.

The Impact of CVE-2019-1920

The vulnerability has a CVSS base score of 7.4, indicating a high severity issue with a potential for a DoS attack on the affected interface.

Technical Details of CVE-2019-1920

Vulnerability Description

Weakness in 802.11r Fast Transition implementation in Cisco IOS Access Points Software
Allows unauthenticated nearby attackers to trigger a DoS situation

Affected Systems and Versions

Product: Cisco Aironet Access Point Software
Vendor: Cisco
Versions Affected: Less than 8.8.100.0

Exploitation Mechanism

Attack Complexity: Low
Attack Vector: Adjacent Network
Availability Impact: High
Privileges Required: None
Scope: Changed
Vector String: CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Mitigation and Prevention

Immediate Steps to Take

Apply vendor-provided patches or updates promptly
Implement network segmentation to limit exposure
Monitor network traffic for any suspicious activity

Long-Term Security Practices

Regularly update and patch all software and firmware
Conduct security training for staff to recognize and respond to potential threats

Patching and Updates

Refer to the vendor's security advisory for specific patch details and instructions