CVE-2021-21976 Explained : Impact and Mitigation

This article provides an overview of CVE-2021-21976, a post-authentication command injection vulnerability in vSphere Replication that could lead to remote code execution.

Understanding CVE-2021-21976

CVE-2021-21976 is a security vulnerability found in vSphere Replication versions 8.3.x, 8.2.x, 8.1.x, and 6.5.x prior to specific patch releases.

What is CVE-2021-21976?

vSphere Replication versions mentioned contain a post-authentication command injection vulnerability. This flaw could be exploited by an authenticated admin user to execute remote code.

The Impact of CVE-2021-21976

The vulnerability enables a malicious user to inject and execute commands, potentially leading to a complete compromise of the affected systems and unauthorized access.

Technical Details of CVE-2021-21976

The following technical aspects of the CVE provide insight into the vulnerability.

Vulnerability Description

vSphere Replication versions mentioned above are susceptible to post-authentication command injection, allowing authenticated admin users to perform remote code execution.

Affected Systems and Versions

The affected products include vSphere Replication 8.3.x, 8.2.x, 8.1.x, and 6.5.x prior to specific patch versions.

Exploitation Mechanism

An authenticated admin user can exploit the vulnerability to inject and execute arbitrary commands on the system, leading to potential remote code execution.

Mitigation and Prevention

To safeguard systems against CVE-2021-21976, the following measures can be implemented.

Immediate Steps to Take

Update vSphere Replication to the patched versions: 8.3.1.2, 8.2.1.1, 8.1.2.3, or 6.5.1.5 to eliminate the vulnerability.

Long-Term Security Practices

Regularly monitor security advisories from VMware and apply patches promptly to mitigate future vulnerabilities.

Patching and Updates

Ensure timely application of security patches provided by VMware to protect systems from known vulnerabilities.