How Often Should You Run Vulnerability Scans?
Vulnerability scanning is one of the simplest ways for businesses to identify security weaknesses before attackers can exploit them.
But one of the most common questions businesses have is: how often should vulnerability scans be performed?
The answer depends on your business, your systems, your compliance requirements, and how often your environment changes. Some businesses may only scan quarterly for compliance. Others may need monthly, weekly, or even continuous scanning depending on their risk level.
Related Clone resources: businesses comparing compliance requirements can also review PCI Scan Cost 2026 and Why a Vulnerability Scan Does Not Automatically Make You PCI Compliant.
This guide explains how often businesses should run vulnerability scans and when additional scans may be needed.
What Is a Vulnerability Scan?
A vulnerability scan is an automated security test that checks systems, websites, applications, networks, or IP addresses for known weaknesses.
- Missing security patches
- Outdated software
- Exposed services
- Weak TLS or SSL settings
- Insecure configurations
- Known vulnerabilities
- Unsupported software versions
- Open ports
- Website security issues
- Internal network risks
The goal is to find vulnerabilities early so they can be reviewed, prioritized, and remediated.
How Often Should Vulnerability Scans Be Performed?
As a general rule, businesses should run vulnerability scans at least quarterly.
However, quarterly scanning should be treated as a minimum, not a best practice for every business.
- Quarterly scans for baseline security and compliance
- Monthly scans for businesses with public-facing systems
- After-change scans whenever major updates or infrastructure changes occur
- More frequent scans for high-risk systems, ecommerce websites, or businesses handling sensitive data
The more often your systems change, the more often you should scan.
How Often Are PCI ASV Scans Required?
For businesses subject to PCI DSS external scanning requirements, PCI ASV scans are generally required at least once every three months.
These scans must be performed by a PCI Approved Scanning Vendor, also known as an ASV. PCI SSC explains that an ASV provides external vulnerability scanning services to validate adherence with PCI DSS external scanning requirements.
For applicable businesses, the scan must pass. If the scan fails, the business needs to fix the findings and rescan until the result meets the required passing criteria.
How Often Should External Vulnerability Scans Be Run?
External vulnerability scans check internet-facing systems. These may include websites, public IP addresses, firewalls, web servers, remote access services, customer portals, ecommerce platforms, and public APIs.
Businesses should run external vulnerability scans at least quarterly, but monthly scanning is often more practical for active environments.
Monthly external scans are useful because public-facing systems are exposed to the internet and may be probed by attackers regularly.
External scans should also be run after major changes, such as:
- Launching a new website
- Adding a new public IP address
- Changing firewall rules
- Moving hosting providers
- Adding remote access services
- Updating ecommerce functionality
- Deploying new applications
- Making major DNS or infrastructure changes
If it is exposed to the internet, it should be scanned regularly.
How Often Should Internal Vulnerability Scans Be Run?
Internal vulnerability scans review systems inside the business network. These may include servers, workstations, internal applications, databases, network devices, and other systems not directly exposed to the public internet.
Internal scans are important because not every attack starts from the outside. If an attacker gains access through phishing, stolen credentials, or an exposed device, internal vulnerabilities can help them move deeper into the environment.
Businesses should consider running internal vulnerability scans monthly or at least quarterly.
Internal scans are especially important for organizations with:
- Multiple office locations
- Remote access tools
- Internal servers
- Sensitive data
- Regulated environments
- Frequent software changes
- Large numbers of endpoints
- Legacy systems
Internal scanning helps businesses understand risk that may not be visible from the outside.
How Often Should Website Security Scans Be Run?
Website security scans should be run regularly, especially when the website supports ecommerce, customer logins, forms, APIs, or payment-related pages.
A website should be scanned:
- Before launch
- After major updates
- After plugin or theme changes
- After hosting changes
- After adding new forms or checkout flows
- After fixing security findings
- On a recurring schedule
For active business websites, monthly scanning is a reasonable starting point. Ecommerce websites and websites that handle sensitive information may need more frequent testing.
This is especially important for websites built with platforms like WordPress, WooCommerce, Magento, Shopify integrations, custom code, or third-party plugins. Website components can become vulnerable over time, even if the website was secure when it launched.
Should You Scan After Every Change?
Not every small update requires a full scan, but significant changes should trigger a new scan.
A significant change may include:
- New servers or cloud resources
- New public IP addresses
- Firewall or network changes
- New applications or APIs
- Major software updates
- Authentication changes
- Payment flow changes
- Ecommerce checkout updates
- New remote access services
- Major website releases
Scanning after significant changes helps confirm that the update did not introduce new vulnerabilities or expose systems unintentionally.
Is Quarterly Scanning Enough?
Quarterly scanning may be enough for some businesses with relatively stable environments, but it is not always enough for active or higher-risk organizations.
For more context on why vulnerability management programs need current vulnerability intelligence, see Clone Systems’ article on NIST’s 2026 NVD changes and vulnerability management.
Quarterly scans can leave long gaps between testing. During that time, new vulnerabilities may be discovered, software may become outdated, and system changes may introduce new risk.
This is why many businesses use quarterly scans for compliance, but monthly scans for practical security monitoring.
A quarterly scan answers: What did our environment look like during this compliance window?
More frequent scanning answers: What does our environment look like now?
What Happens If a Vulnerability Scan Finds Issues?
A vulnerability scan is only useful if the findings are reviewed and addressed.
After a scan, businesses should:
- Review the findings
- Prioritize high-risk vulnerabilities
- Confirm which systems are affected
- Assign remediation ownership
- Patch or reconfigure systems
- Remove unnecessary exposed services
- Document exceptions where appropriate
- Rescan to confirm fixes worked
A scan report should not sit unused. The value comes from turning findings into remediation actions.
Vulnerability Scanning vs Penetration Testing
Vulnerability scanning and penetration testing are related, but they are not the same.
A vulnerability scan identifies known weaknesses. It is usually automated and can be performed regularly.
A penetration test goes deeper. It evaluates whether vulnerabilities can be exploited and how much risk they create in a real-world scenario.
Most businesses benefit from both:
- Vulnerability scanning for regular visibility
- Penetration testing for deeper validation
- Rescanning to confirm remediation
- Internal and external testing for broader coverage
Vulnerability scanning helps identify possible issues. Penetration testing helps determine how serious those issues may be.
Recommended Vulnerability Scanning Schedule
| Scan Type | Recommended Frequency |
| PCI ASV scan | At least quarterly, where applicable |
| External vulnerability scan | Quarterly minimum, monthly preferred |
| Internal vulnerability scan | Monthly or quarterly |
| Website security scan | Monthly and after major changes |
| Ecommerce website scan | Monthly, after changes, and for PCI where applicable |
| Penetration test | Annually or after major application changes |
| Rescan after remediation | After fixes are completed |
How to Choose the Right Scanning Frequency
When deciding how often to scan, businesses should consider:
- How many systems are exposed to the internet
- Whether the business handles sensitive data
- Whether PCI DSS, HIPAA, SOC 2, or other requirements apply
- How often websites, applications, or infrastructure change
- Whether remote access services are in use
- Whether internal systems are segmented
- Whether the business has had previous security findings
- Whether customers, banks, or partners require reports
A small static website may not need the same scanning schedule as an ecommerce business, SaaS provider, healthcare company, or organization with multiple locations.
Not Sure How Often You Should Be Scanning?
Whether you need quarterly PCI ASV scans for compliance or monthly external scans for active environments, Clone Systems has a scanning plan that fits. Start online or contact us to find the right frequency for your business.
Final Thoughts
Businesses should run vulnerability scans at least quarterly, but quarterly scanning should not be treated as enough for every environment.
Public-facing systems, ecommerce websites, internal networks, and sensitive applications often need more frequent scanning. Businesses should also scan after significant changes and rescan after remediation to confirm that issues have been fixed.
The best vulnerability scanning schedule is one that gives your business regular visibility into risk and enough time to fix problems before they become security incidents.
Clone Systems helps businesses identify and manage security risks through PCI ASV scanning, external vulnerability scanning, internal vulnerability scanning, website security scanning, automated penetration testing, and managed penetration testing.
Ready to start scanning? Purchase Vulnerability Assessment Scanning or contact Clone Systems for help choosing the right scanning frequency for your environment.
Source Notes
PCI Security Standards Council: Approved Scanning Vendors program and PCI DSS external vulnerability scanning guidance.
PCI Security Standards Council: PCI DSS Requirement 11.3.2 guidance and quarterly scanning expectations for applicable entities.
