CVE-2019-16022 : Vulnerability Insights and Analysis

Cisco IOS XR Software BGP EVPN Denial of Service Vulnerabilities

Understanding CVE-2019-16022

This CVE involves weaknesses in Cisco IOS XR Software's implementation of the Border Gateway Protocol (BGP) Ethernet VPN (EVPN) functionality, potentially leading to a denial of service (DoS) situation.

What is CVE-2019-16022?

The vulnerabilities stem from improper handling of BGP update messages containing manipulated EVPN attributes. An attacker could exploit this by sending malformed BGP EVPN update messages to a vulnerable system, causing an unexpected restart of the BGP process and a DoS condition.

The Impact of CVE-2019-16022

CVSS Score: 8.6 (High)
Attack Vector: Network
Availability Impact: High
Scope: Changed
These vulnerabilities could allow an unauthenticated attacker to trigger a DoS condition.

Technical Details of CVE-2019-16022

Vulnerability Description

The vulnerabilities arise from incorrect processing of BGP update messages with crafted EVPN attributes.

Affected Systems and Versions

Product: Cisco IOS XR Software
Vendor: Cisco
Affected Version: Unspecified

Exploitation Mechanism

Attacker sends malformed BGP EVPN update messages to a vulnerable system
Exploitation requires the message to originate from a valid BGP peer or be injected into the victim's BGP network via a valid TCP connection.

Mitigation and Prevention

Immediate Steps to Take

Apply patches or updates provided by Cisco
Implement network segmentation to limit exposure

Long-Term Security Practices

Regularly monitor and update BGP configurations
Conduct security assessments to identify vulnerabilities

Patching and Updates

Stay informed about security advisories from Cisco
Apply security patches promptly to mitigate risks