External vs Internal Vulnerability Scans: Difference Explained

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A vulnerability scan examines both internal and external IT systems to find weaknesses that hackers may take advantage of. By carrying out these scans, you can boost your cybersecurity defenses and keep your company safe from cyber attacks by identifying and addressing vulnerabilities before they are exploited.

External and internal vulnerability scans are like your organization’s superpower duo when it comes to protecting against system weaknesses. We’ll cover their uses and benefits in detail, but here’s a high-level overview to start:

  • External vulnerability scan: Tests the network security of your company from the outside in order to find vulnerabilities and strengthen defenses against outside attacks.
  • Internal vulnerability scan: A detailed examination of the internal network, systems, and infrastructure of your company to spot weaknesses and improve internal security measures.

Here’s a quick look at the difference between External and Internal Vulnerability Scans:

AspectExternal ScanInternal Scan
PurposeDefend against external threatsEnhance internal security, protect against lateral movement
ScopeExternal-facing assetsInternal network and systems
MethodsEthical hacking, red teams, pentestsVulnerability scans, patching, mitigation
Use CasesProtect from external attacksMitigate internal risks
BenefitsExternal threat protectionInternal security improvement
FrequencyPeriodic or in response to changesRegular for internal security
ToolsQualys, Rapid InsightVM, etc. Qualys, Rapid InsightVM, etc.
ApproachIdentify external vulnerabilitiesDiscover internal vulnerabilities
ReportingSeverity ratings, remediation infoInternal vulnerability reports
CollaborationExternal security teamsInternal IT and security teams
ComplianceExternal standards/regulationsInternal security policies, regulations

See the Best Vulnerability Scanner Tools

Jump ahead to:

What Are External Vulnerability Scans?

An external vulnerability scan involves simulating attacks on your external-facing systems to identify potential weaknesses that malicious hackers could exploit, similar to an automated penetration test. By proactively uncovering vulnerabilities, you can strengthen your defenses and protect your systems and data. It’s like having a vigilant security guard checking your digital perimeter, ensuring that your organization is well-protected against external threats.

4 Benefits of External Vulnerability Scans

External vulnerability scans play a key role in protecting your network from intruders.

  • Verify external security posture
  • Identify weakness that can potentially lead to a breach of security
  • Identify significant threats and risks in the enterprise network
  • Pinpoint new devices or services that may pose potential threats or weaknesses to the enterprise

Common External Vulnerability Risks Found

External scans can uncover a range of cyber risks for security teams to address. These include:

When Should You Do an External Vulnerability Scan?

External vulnerability scans are conducted based on the size of your organization, with different frequencies for small and large enterprises. While larger organizations typically require multiple scans throughout the year to ensure optimal network security and the highest level of protection, small businesses or organizations may find it sufficient to conduct these scans once a year.

However, it is important to note that the frequency of vulnerability scans should always be adjusted based on the evolving threat landscape and the specific security needs of each organization, regardless of its size. By regularly assessing vulnerabilities through these scans, organizations of all sizes can proactively identify and address potential security weaknesses, fortifying their networks against potential breaches.

Also read: Penetration Testing vs. Vulnerability Testing: An Important Difference

What Are Internal Vulnerability Scans?

Internal vulnerability scan focuses on identifying weaknesses that could have evaded your exterior defenses. It’s like having someone who is familiar with every obscure crevice of your business looking for any openings that may be used by nefarious insiders or skilled attackers who have already gotten past your outward defenses and are trying to move laterally through your network.

You may find and fix these weaknesses inside by doing internal vulnerability scans, which will guarantee that your company’s crucial assets and confidential information are well-protected. This gives you peace of mind and enables you to keep one step ahead of potential assaults by acting as an additional layer of security against dangers that may be hiding inside your digital fortress.

5 Benefits of Internal Vulnerability Scans

Internal scans are an important line of defense that can prevent malicious actors from reaching critical applications and data. Benefits of internal vulnerability scans include:

  • Simulates behaviors and actions of an internal hacker to identify vulnerabilities
  • Validates insider access
  • Identify and prioritize vulnerabilities for remediation
  • Provide insights to improve patch and security management
  • Fix and improve compliance with regulatory requirements and security standards

Common Internal Vulnerability Risks Found

Internal scans can uncover a range of serious threats:

  • Unauthorized PCs and mobile devices
  • IoT devices (Wi-Fi TVs, etc.) and connected industrial equipment
  • Vulnerable password practices
  • Unauthorized access levels
  • Unauthorized data disclosure
  • Insufficient system maintenance
  • Non-protected computer stations
  • Insecure internal network applications

When Should You Do an Internal Vulnerability Scan?

Internal vulnerability scans are essential for maintaining your organization’s internal network security, systems, and applications. They simulate potential attacks from insiders, compromised devices, or accounts. Large organizations must regularly perform these scans to monitor their network security, as they can still be at risk due to factors like insider threats, misconfigurations, or compromised user accounts. By conducting these scans, large organizations can spot vulnerabilities and take prompt action to reduce the chances of unauthorized access and data breaches. Small organizations should also consider internal vulnerability scans, as they can uncover security weaknesses that might slip under the radar.

Regular internal scans give them an edge, allowing your organization to maintain a higher level of security and protect critical assets. Both large and small organizations must proactively identify and address vulnerabilities to strengthen defenses and safeguard valuable information.

See the Top Data Loss Prevention (DLP) Solutions

Should You Do Both?

It is advisable to do both external and internal vulnerability scans to guarantee complete protection for a company’s digital assets. Let’s explore when and why it is suitable to carry out both scans.

External scans are used to evaluate the security of a company’s networks and systems that are accessible from the outside. In order to do this, the network perimeter must be probed, public IP addresses must be checked, and potential external access points must be assessed. Organizations learn about vulnerabilities that outside attackers trying to penetrate their defenses may exploit by conducting external scans.

The goal of internal vulnerability scans, on the other hand, is to locate weak points and vulnerabilities within a company’s internal network and systems. These scans usually concentrate on items like servers, workstations, and software that are located inside the company’s network borders. Even if they are not immediately accessible to the internet, enterprises can identify particular security holes and configuration errors that may be present inside the network by executing vulnerability scans.

Why then should we run both kinds of scans? It’s because they cover different aspects of the security environment and have different functions.

External scans are essential for evaluating the security posture from the viewpoint of an adversary. Organizations can find weaknesses that might be exposed to online criminals by simulating potential external attacks. By doing so, they may improve their defenses, fix weaknesses, and lower the probability of successful assaults.

Both external and internal vulnerability scans give a more detailed picture of flaws. They assist businesses in identifying security holes that both internal and external attackers might exploit in their network architecture, applications, or systems. Organizations may improve overall security posture and lower the likelihood of data breaches, illegal access, or other security events by addressing these different vulnerabilities.

When Is The Best Time to Conduct External & Internal Scans?

The best time to do these scans depends on a number of factors. Organizations should typically conduct periodic external scans to identify changes to their external attack surface and swiftly patch any newly discovered vulnerabilities. This might be carried out every month, every three months, or whenever there are network environment changes (such as infrastructure updates or website modifications).

Ideally, external and internal vulnerability scans have to be carried out often as well. The frequency may vary depending on the size, sector, legal requirements, and risk tolerance of the company. For instance, larger companies with more complicated networks could do vulnerability checks on a weekly or monthly basis, whereas smaller companies might choose to do so just once every three months. To maintain the environment’s continuing security, vulnerability checks should also be carried out following any substantial program upgrades or infrastructure modifications.

Organizations may proactively discover and resolve security gaps, both from external threats and internal vulnerabilities, by conducting external and vulnerability scans. With this all-encompassing strategy, they can strengthen their defenses, shrink the attack surface, and decrease possible risks, eventually protecting their digital assets and upholding a strong security posture.

Also read: 12 Types of Vulnerability Scans & When to Run Each

Bottom Line: External vs Internal Vulnerability Scans

External and internal vulnerability scans are the dynamic duo that you need to protect your organization from potential threats. Internal scans go deeply into your internal systems to stop threats that could slip past your outside defenses, while external scans concentrate on bolstering your network security by simulating assaults from the outside. You can proactively find and fix vulnerabilities, improve your overall security posture, and protect your sensitive data by carrying out both types of scans.

Depending on the size and unique requirements of your firm, the frequency of these scans may vary, but ongoing evaluations are essential to keep ahead of emerging risks. Remember that you can keep your digital assets safe and maintain a powerful defense against cyberattacks by combining the capabilities of external and internal vulnerability scans.

Further reading:

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