CVE-2020-1626 Explained : Impact and Mitigation

Juniper Networks Junos OS Evolved is affected by a Denial of Service vulnerability that can be triggered by sending specific packets to the device, leading to a process crash and service disruption.

Understanding CVE-2020-1626

This CVE entry addresses a critical Denial of Service vulnerability in Junos OS Evolved that impacts packet forwarding functionality.

What is CVE-2020-1626?

A vulnerability in Junos OS Evolved allows attackers to execute a Denial of Service attack by flooding the device with specific packets, causing the pfemand process to crash and disrupting service.

The Impact of CVE-2020-1626

Attack Complexity: Low
Attack Vector: Network
Availability Impact: High
Base Score: 7.5 (High)
Privileges Required: None

The vulnerability poses a significant risk to the availability of affected systems without requiring privileges for exploitation.

Technical Details of CVE-2020-1626

The following technical aspects are pertinent to understanding the vulnerability.

Vulnerability Description

The vulnerability allows attackers to trigger a Denial of Service condition by flooding Junos OS Evolved with specific packets, leading to the crash of the pfemand process responsible for packet forwarding.

Affected Systems and Versions

Product: Junos OS Evolved
Vendor: Juniper Networks
Vulnerable Versions: All versions before 19.1R1-EVO

Exploitation Mechanism

The attacker can exploit this vulnerability by sending a high rate of specific packets to the device, causing the pfemand process to crash and resulting in a sustained Denial of Service.

Mitigation and Prevention

To address CVE-2020-1626 and enhance system security, consider the following mitigation strategies.

Immediate Steps to Take

Implement access lists or firewall filters to restrict access to known TCP and UDP ports.
Allow access only from trusted administrative networks or hosts to minimize the risk of exploitation.

Long-Term Security Practices

Regularly monitor network traffic for unusual patterns or high packet rates.
Stay informed about security advisories and updates provided by Juniper Networks.

Patching and Updates

Update to the following software releases or later versions to mitigate the vulnerability: 19.1R1-EVO, 19.2R1-EVO, 19.3R1-EVO, and subsequent releases.