CVE-2023-44186 Explained : Impact and Mitigation

This article discusses a Denial of Service (DoS) vulnerability in Juniper Networks Junos OS and Junos OS Evolved, where an attacker can exploit the AS PATH processing to trigger a sustained DoS condition. Learn about the impact, affected systems, exploitation mechanism, and mitigation steps.

Understanding CVE-2023-44186

This CVE-2023-44186 vulnerability affects Juniper Networks Junos OS and Junos OS Evolved, allowing attackers to exploit BGP update messages to trigger a Denial of Service condition.

What is CVE-2023-44186?

An Improper Handling of Exceptional Conditions vulnerability in AS PATH processing of Juniper Networks Junos OS and Junos OS Evolved allows attackers to exploit BGP update messages, affecting the availability of the system.

The Impact of CVE-2023-44186

This vulnerability can lead to a sustained Denial of Service (DoS) condition when a BGP update message with a large number of 4-byte ASes is sent, affecting routers with Non-Stop Routing (NSR) enabled.

Technical Details of CVE-2023-44186

Vulnerability Description

The vulnerability arises from improper AS PATH processing in Juniper Networks Junos OS and Junos OS Evolved, allowing DoS attacks through BGP update messages.

Affected Systems and Versions

Junos OS versions prior to 23.2R2 and Junos OS Evolved versions before 23.2R2-EVO are affected by this vulnerability.

Exploitation Mechanism

Attackers can send BGP update messages with a long AS PATH to trigger the vulnerability, leading to a sustained DoS condition.

Mitigation and Prevention

Immediate Steps to Take

Limit AS PATH length using the provided example configuration to mitigate the risk of this vulnerability.

Long-Term Security Practices

Follow operational and security best practices to enhance network security and prevent such DoS attacks.

Patching and Updates

Update to the latest software releases that address this specific issue for Junos OS and Junos OS Evolved.