ASV Scan Requirements: Approved Scanning Vendor Guide

Introduction

Approved Scanning Vendor (ASV) scans are a critical component of PCI DSS compliance that many businesses struggle to understand and implement correctly. These mandatory external vulnerability scans help identify security weaknesses in your cardholder data environment that could be exploited by cybercriminals.

Whether you’re a small e-commerce retailer or a large enterprise, understanding ASV scan requirements is essential for maintaining PCI compliance and protecting sensitive payment card data. Failure to conduct proper ASV scans can result in compliance violations, hefty fines, and increased vulnerability to data breaches.

In this comprehensive guide, you’ll learn everything you need to know about ASV scans, including who needs them, how they work, implementation steps, and best practices. By the end, you’ll have the knowledge and tools necessary to successfully integrate ASV scanning into your PCI compliance program.

Core Concepts

What is an ASV Scan?

An Approved Scanning Vendor (ASV) scan is an external vulnerability assessment conducted by a PCI Security Standards Council-approved company. These scans examine your external-facing systems and networks to identify security vulnerabilities that could compromise cardholder data.

ASV scans are automated assessments that test for known vulnerabilities, misconfigurations, and security weaknesses from an external perspective—simulating how an attacker might view your systems from the internet. The scan results must show a “passing” status to maintain PCI compliance.

Key Terminology

ASV: Approved Scanning Vendor – A company authorized by the PCI SSC to conduct external vulnerability scans
External Scan: Vulnerability assessment conducted from outside your network perimeter
Passing Scan: A scan that shows no vulnerabilities rated 4.0 or higher on the CVSS scale
Scan Report: Documentation of scan results required for PCI compliance validation
Remediation: The process of fixing identified vulnerabilities

PCI DSS Integration

ASV scans fulfill PCI DSS Requirement 11.2.2, which mandates quarterly external vulnerability scans by an approved vendor. This requirement applies to all merchants and service providers that store, process, or transmit cardholder data, regardless of their compliance level (Level 1-4).

The scans must cover all external IP addresses and systems that could impact the security of the cardholder data environment (CDE). This includes web servers, firewalls, DNS servers, and any other internet-facing systems.

Regulatory Context

The PCI Security Standards Council established ASV requirements to ensure consistent, standardized external vulnerability assessments across the payment card industry. Only companies that meet strict qualification criteria and pass rigorous testing can become approved scanning vendors.

ASV scans complement other PCI requirements like internal vulnerability scanning, penetration testing, and security assessments to create a comprehensive security evaluation framework.

Requirements Breakdown

What’s Required

Quarterly External Scans: You must conduct ASV scans at least once every quarter (every three months). The scans must be performed by a PCI SSC-approved scanning vendor—you cannot use internal staff or non-approved third parties.

Passing Results: All quarterly scans must achieve a “passing” status, meaning no vulnerabilities with a CVSS score of 4.0 or higher are present. Any high-risk vulnerabilities must be remediated and the affected systems re-scanned until they pass.

After Significant Changes: In addition to quarterly scans, you must conduct ASV scans after any significant changes to your network or applications that could impact security. This includes system upgrades, new deployments, or infrastructure modifications.

Complete Documentation: You must maintain scan reports and evidence of remediation activities. These documents are required during compliance assessments and audits.

Who Must Comply

All Merchant Levels: ASV scanning is required for all PCI DSS merchant levels (1-4), regardless of transaction volume or compliance validation method. This includes businesses that:

Process credit card transactions online
Store cardholder data in any format
Have internet-facing systems connected to the CDE
Transmit cardholder data over public networks

Service Providers: All service providers that handle cardholder data must also conduct quarterly ASV scans of their external-facing systems.

Exemptions: The only entities exempt from ASV scanning are those with no external IP addresses or internet-facing systems connected to their cardholder data environment.

Validation Methods

Self-Assessment Questionnaires (SAQ): Most merchants validate ASV compliance through SAQs, which include specific attestations about quarterly scanning and remediation activities.

Report on Compliance (ROC): Level 1 merchants and service providers must document ASV scan compliance in their ROC, including evidence of quarterly scans and vulnerability remediation.

Attestation of Compliance (AOC): All entities must confirm ASV scan compliance in their AOC, certifying that scans are conducted quarterly and vulnerabilities are properly addressed.

Implementation Steps

Step 1: Select an Approved Scanning Vendor

Research and choose an ASV from the PCI Security Standards Council’s official list. Consider factors such as:

Pricing and scan frequency options
Report quality and detail level
Customer support availability
Integration with your existing security tools
Remediation guidance and assistance

Timeline: 1-2 weeks for vendor selection and contract execution.

Step 2: Define Scan Scope

Work with your chosen ASV to identify all external IP addresses and systems that must be included in the scan scope. This typically includes:

Web servers hosting payment applications
External firewalls and network devices
DNS servers and mail servers
Any other internet-facing systems connected to the CDE

Timeline: 1 week for scope definition and validation.

Step 3: Schedule Initial Scan

Coordinate with your ASV to schedule the first vulnerability scan. Consider:

Business impact and maintenance windows
Staff availability for remediation activities
Integration with change management processes
Communication with stakeholders

Timeline: Scans typically complete within 24-48 hours of initiation.

Step 4: Review Results and Remediate

Analyze scan results and develop a remediation plan for any identified vulnerabilities:

Prioritize high and medium-risk vulnerabilities
Assign responsibility for remediation activities
Set target completion dates
Track progress and verify fixes

Timeline: 1-4 weeks depending on vulnerability complexity and organizational resources.

Step 5: Conduct Remediation Scans

After addressing vulnerabilities, request remediation scans to verify fixes and achieve passing status:

Most ASVs provide unlimited remediation scans
Focus scans on previously vulnerable systems
Document all remediation activities

Timeline: 1-3 days per remediation cycle.

Step 6: Establish Ongoing Process

Implement procedures for quarterly scanning and ongoing vulnerability management:

Set calendar reminders for quarterly scans
Assign roles and responsibilities
Integrate with change management
Plan for continuous monitoring

Best Practices

Industry Recommendations

Automate Where Possible: Use automated scheduling and notification features to ensure scans occur on time. Many ASVs offer automated quarterly scanning with email notifications.

Integrate with SDLC: Include ASV scanning in your software development lifecycle and change management processes. Conduct scans before and after major deployments.

Maintain Asset Inventory: Keep an accurate inventory of all external-facing assets to ensure complete scan coverage. Regular reviews help identify scope changes.

Efficiency Tips

Coordinate Timing: Schedule ASV scans to coincide with internal vulnerability assessments and penetration testing for comprehensive security evaluation.

Prepare Response Teams: Ensure technical staff are available during scan periods to address any issues that arise and begin immediate remediation.

Use Multiple Windows: Consider scanning during multiple maintenance windows to minimize business impact and ensure coverage of all systems.

Cost-Saving Strategies

Annual Contracts: Most ASVs offer discounts for annual contracts versus quarterly purchases. This also ensures consistent vendor relationships.

Bundle Services: Look for ASVs that offer additional services like internal scanning, compliance consulting, or managed security services at reduced rates.

Efficient Remediation: Focus on systematic vulnerability management to reduce the number of remediation scans needed and associated costs.

Common Mistakes

What to Avoid

Incomplete Scope Definition: Failing to include all external-facing systems connected to the CDE is a critical error that can result in compliance violations. Many organizations overlook development servers, staging environments, or legacy systems.

Ignoring Low-Risk Vulnerabilities: While only high-risk vulnerabilities prevent passing scans, ignoring medium and low-risk issues creates accumulated security debt that becomes expensive to address later.

Poor Timing: Scheduling scans during critical business periods or without adequate remediation time can create unnecessary stress and compliance risks.

How to Fix Issues

Scope Gaps: Conduct regular asset discovery and network mapping to identify all external-facing systems. Document any scope changes and update ASV configurations accordingly.

Remediation Delays: Establish clear SLAs for vulnerability remediation and escalation procedures when timelines are missed. Consider temporary compensating controls for complex fixes.

Process Breakdowns: Implement formal change management procedures that trigger ASV scans after significant modifications to external-facing systems.

When to Escalate

Repeated Failures: If systems consistently fail ASV scans due to the same vulnerabilities, escalate to senior management and consider additional security investments.

Resource Constraints: When remediation requires significant resources or budget allocation beyond IT authority levels, escalate to appropriate decision-makers.

Compliance Deadlines: If quarterly scan deadlines are at risk due to remediation delays, escalate immediately to ensure compliance obligations are met.

Tools and Resources

Helpful Tools

Vulnerability Management Platforms: Tools like Nessus, Qualys, or Rapid7 can complement ASV scans with internal vulnerability assessments and continuous monitoring.

Asset Discovery Tools: Solutions like Lansweeper, ManageEngine AssetExplorer, or Spiceworks help maintain accurate inventories of external-facing systems.

Configuration Management: Tools like Ansible, Puppet, or Chef can help maintain secure configurations and accelerate vulnerability remediation.

Templates and Checklists

ASV Vendor Evaluation Matrix: Create standardized criteria for comparing ASV providers, including pricing, features, and service levels.

Scan Preparation Checklist: Develop checklists to ensure consistent scan preparation, including scope validation, stakeholder notification, and resource allocation.

Remediation Tracking Templates: Use spreadsheets or ticketing systems to track vulnerability remediation progress and ensure nothing falls through the cracks.

Professional Services

PCI Consulting: Engage qualified security assessors (QSAs) for complex compliance scenarios or audit preparation assistance.

Managed Security Services: Consider managed vulnerability scanning and remediation services for organizations with limited internal security resources.

Penetration Testing: Supplement ASV scans with annual penetration testing to identify business logic flaws and complex attack vectors that automated scans might miss.

FAQ

1. How often must ASV scans be performed?

ASV scans must be conducted at least quarterly (every three months) and after any significant changes to your network or applications. Most organizations schedule scans monthly to ensure consistent coverage and easier remediation management.

2. Can I perform ASV scans internally instead of using an approved vendor?

No, external vulnerability scans for PCI compliance must be conducted by a PCI Security Standards Council-approved scanning vendor. Internal scans can supplement but never replace ASV scans for compliance purposes.

3. What happens if my ASV scan fails?

Failed scans must be remediated and re-scanned until they achieve passing status. You cannot maintain PCI compliance with failing ASV scans. Most ASVs provide unlimited remediation scans to help you achieve compliance.

4. Do I need ASV scans if I use a hosted payment solution?

It depends on your environment and SAQ type. If you have no external-facing systems connected to cardholder data processing (such as SAQ A merchants), ASV scans may not be required. However, most merchants with any payment infrastructure need quarterly ASV scans.

5. How long do ASV scan results remain valid?

ASV scan results are valid for one quarter (three months) from the scan date. You must conduct new scans at least every 90 days to maintain compliance, and scans must be current during any compliance assessments or audits.

Conclusion

ASV scanning is a fundamental requirement for PCI DSS compliance that helps protect your organization and customers from cybersecurity threats. By understanding the requirements, implementing proper processes, and following industry best practices, you can ensure your ASV scanning program effectively supports your overall security posture.

Success with ASV scanning requires ongoing commitment, adequate resources, and integration with your broader security and compliance initiatives. Regular monitoring, prompt remediation, and continuous process improvement will help you maintain compliance while strengthening your security defenses.

Remember that ASV scanning is just one component of a comprehensive PCI compliance program. Combining quarterly external scans with internal vulnerability assessments, security awareness training, and other PCI requirements creates a robust defense against payment card data breaches.

Ready to start your PCI compliance journey? Try our free PCI SAQ Wizard tool at PCICompliance.com to determine which Self-Assessment Questionnaire you need and get step-by-step guidance for achieving compliance. PCICompliance.com helps thousands of businesses achieve and maintain PCI DSS compliance with affordable tools, expert guidance, and ongoing support.