28 Jan 2025

Protecting VMware Avi Load Balancer from Critical SQL Injection Vulnerability (VMSA-2025-0002)

Demetrios S Mustakas Jr

Introduction

Today, VMware disclosed a significant security vulnerability VMSA-2025-0002 (CVE-2025-22217) impacting its Avi Load Balancer platform. With a CVSSv3 score of 8.6 (Important), this unauthenticated blind SQL injection flaw has the potential to severely compromise critical systems, making it essential for organizations using this platform to act swiftly.

Here’s what you need to know about the vulnerability, its implications, and how to protect your environment.

What is VMware Avi Load Balancer?

The VMware Avi Load Balancer is a cutting-edge application delivery controller used in modern data centers and cloud environments. Its key features include:

1. Load Balancing: Ensures high availability and reliability by distributing traffic across multiple servers.
2. Application Monitoring: Provides real-time insights into application health and performance.
3. Automation: Scales applications dynamically based on demand.
4. Security: Offers Web Application Firewall (WAF), SSL/TLS offloading, and more.

This platform plays a critical role in ensuring seamless application performance and availability. Given its strategic position, a compromise could have widespread consequences.

Understanding the Vulnerability - What is an Unauthenticated Blind SQL Injection?

An unauthenticated blind SQL injection is a web security flaw where attackers execute arbitrary SQL queries on a backend database without needing valid credentials. Unlike traditional SQL injection, the attacker does not directly see the query results but infers information based on the system’s behavior or response times.

How It Works:

1. Entry Point: The attacker identifies a vulnerable input field or API endpoint.
2. Injection: Malicious SQL queries are sent to the application.
3. Exploitation: Observing application errors, delays, or true/false conditions to extract information. Manipulating database contents or obtaining sensitive data.

Impacted Versions:

This vulnerability impacts the following versions of VMware Avi Load Balancer:

1. 30.1.1 & 30.1.2
2. 30.2.1 & 30.2.2

Notably, versions 21.x and 22.x are not affected. Additionally, if you are running version 30.1.1, you must first upgrade to 30.1.2 or later before applying the patch.

Implications for Your Organization

This vulnerability allows attackers to:

1. Compromise the Database: Extract sensitive data, such as SSL certificates and user credentials. Harvest internal configuration details that could aid in lateral movement.
2. Service Disruption: Alter critical database contents, potentially affecting load balancing operations and causing application downtime.
3. Privilege Escalation: Use the database as a foothold to compromise other systems in your environment.

Mitigation and Next Steps

Apply the Patch:

VMware has released fixed versions for affected systems:

1. 30.1.1 / 30.1.2: Upgrade to 30.1.2-2p2.
2. 30.2.1: Upgrade to 30.2.1-2p5.
3. 30.2.2: Upgrade to 30.2.2-2p2.

No workarounds are available, patching is the only way to remediate this vulnerability.

Additional Best Practices:

1. Secure Input Validation: Sanitize user inputs and use parameterized queries to prevent injection attacks.
2. Network Segmentation: Restrict access to the Avi Controller to trusted networks or IP ranges.
3. Database Hardening: Limit database permissions and monitor for suspicious queries.
4. Monitoring and Logging: Use application and database monitoring tools to detect anomalies.

The Bottom Line

VMSA-2025-0002 highlights the importance of proactive security measures in protecting critical infrastructure. If you’re using VMware Avi Load Balancer, prioritize patching the affected systems immediately to prevent potential exploitation.

For organizations that depend on application delivery controllers, this vulnerability underscores the need for regular vulnerability assessments and robust security configurations. If you have concerns about this vulnerability or any other VMware vSphere security issue, we encourage you to reach out to our professional advisory services for guidance and tailored recommendations.

References

1. VMware Security Advisory: VMSA-2025-0002
2. Understanding Unauthenticated SQL Injections (OWASP)
3. VMware Avi Load Balancer Reference Architecture