CVE-2021-28510 : What You Need to Know

Arista Networks published CVE-2021-28510, affecting systems running EOS due to a Precision Time Protocol (PTP) packet vulnerability. This article provides insights into the impact, technical details, and mitigation strategies for this CVE.

Understanding CVE-2021-28510

This section delves into the specifics of CVE-2021-28510.

What is CVE-2021-28510?

CVE-2021-28510 impacts systems running EOS by causing the PTP agent to restart due to an invalid Type-Length-Value (TLV) in a PTP packet.

The Impact of CVE-2021-28510

The vulnerability results in repeated restarts of the service, rendering it unavailable for users.

Technical Details of CVE-2021-28510

Explore the technical aspects of CVE-2021-28510 below.

Vulnerability Description

The PTP packet vulnerability triggers service unavailability by causing the PTP agent to restart.

Affected Systems and Versions

The vulnerability affects Arista EOS versions 4.22, 4.27.1, 4.26.4, 4.25.6, 4.24.8, and 4.23.10.

Exploitation Mechanism

Attackers exploit the vulnerability by sending PTP packets with invalid TLV, leading to service disruption.

Mitigation and Prevention

Discover the steps to mitigate and prevent CVE-2021-28510.

Immediate Steps to Take

Install ACL rules to block PTP packets from untrusted sources and restrict access to non-management networks.

Long-Term Security Practices

Upgrade to the latest EOS software version to prevent the exploitation of this vulnerability.

Patching and Updates

Arista recommends upgrading to specific versions to address CVE-2021-28510. Hotfixes are also available for remediation.