CVE-2019-1909 : Exploit Details and Defense Strategies

Cisco IOS XR Software Border Gateway Protocol Denial of Service Vulnerability

Understanding CVE-2019-1909

This CVE involves a vulnerability in Cisco IOS XR Software's implementation of Border Gateway Protocol (BGP) functionality, potentially leading to a denial of service (DoS) attack.

What is CVE-2019-1909?

The vulnerability in Cisco IOS XR Software arises from the incorrect handling of specific BGP update messages, allowing unauthorized remote attackers to exploit the system and cause a DoS condition.

The Impact of CVE-2019-1909

The vulnerability could lead to a situation where the affected system experiences a denial of service (DoS) due to the incorrect processing of certain BGP update messages.

Technical Details of CVE-2019-1909

Vulnerability Description

The vulnerability is in the way Cisco IOS XR Software implements BGP functionality
Attackers can exploit this by sending BGP update messages with specific attributes
Successful exploitation can lead to an unexpected restart of the BGP process

Affected Systems and Versions

Product: Cisco IOS XR Software
Vendor: Cisco
Versions Affected: Less than 6.4.2

Exploitation Mechanism

Attack Complexity: High
Attack Vector: Network
Availability Impact: High
Base Score: 6.8 (Medium Severity)
The attacker needs no privileges and no user interaction to exploit the vulnerability

Mitigation and Prevention

Immediate Steps to Take

Apply the necessary security patches provided by Cisco
Monitor network traffic for any suspicious activity related to BGP

Long-Term Security Practices

Regularly update and patch all software and systems
Implement network segmentation and access controls to limit exposure

Patching and Updates

Stay informed about security advisories from Cisco
Regularly check for updates and apply them promptly