CVE-2021-28496 Explained : Impact and Mitigation

A detailed overview of CVE-2021-28496 affecting Arista EOS software versions, leading to sensitive data leakage and potential security risks.

Understanding CVE-2021-28496

This section delves into the impact, technical details, and mitigation strategies related to the CVE-2021-28496 vulnerability.

What is CVE-2021-28496?

CVE-2021-28496 affects systems running Arista EOS and CloudEOS with specific release versions, potentially leaking sensitive configurations related to shared secret profiles.

The Impact of CVE-2021-28496

The vulnerability can lead to the leakage of BiDirectional Forwarding Detection (BFD) passwords when displaying output over eAPI or other JSON outputs to authenticated users, posing potential security risks.

Technical Details of CVE-2021-28496

This section provides details on the vulnerability description, affected systems, versions, and exploitation mechanisms.

Vulnerability Description

The flaw allows password leakage for BFD configurations when using shared secret profiles on affected Arista EOS versions, potentially exposing sensitive data.

Affected Systems and Versions

Arista EOS versions up to 4.26.1 are affected, including specific releases in the 4.22.x to 4.26.x trains.

Exploitation Mechanism

The vulnerability can be exploited by displaying output over eAPI or other JSON outputs to authenticated users on the device, resulting in the leakage of confidential information.

Mitigation and Prevention

This section outlines immediate steps, long-term security practices, and patching solutions to mitigate the CVE-2021-28496 vulnerability.

Immediate Steps to Take

Implement restrictions on access to the related CLI show command for specified role types to mitigate the vulnerability.

Long-Term Security Practices

Enforce role-based authorization mechanisms to ensure secure data handling and prevent leakage of sensitive configurations.

Patching and Updates

Upgrade to remediated software versions or apply hotfix SWIX available from Arista to address the vulnerability. Ensure running EOS versions 4.23.10 and later, 4.24.8 and later, 4.25.5 and later, or 4.26.2 and later to resolve the issue.