Microsoft Defender External Attack Surface Management vs. Tenable Nessus

Microsoft Defender External Attack Surface Management is particularly well-suited for discovering, inventorying, and continuously monitoring the external attack surface, especially in environments with heavy Microsoft adoption. It is less suitable as a standalone solution for internal scanning, real-time attack detection, automated remediation, or advanced application testing. Microsoft Defender External Attack Surface Management es especialmente adecuado para descubrir, inventariar y monitorear continuamente la superficie de ataque externa, sobre todo en entornos con fuerte adopción de Microsoft. Es menos adecuado como solución única para escaneo interno, detección de ataques en tiempo real, remediación automática o pruebas avanzadas de aplicaciones. Parts of this review were originally written in Spanish and have been translated into English using a third-party translation tool. While we strive for accuracy, some nuances or meanings may not be perfectly captured.

Incentivized

It is an excellent tool for scanning servers, workstations, and network devices to identify missing patches and misconfiguration; we regularly use it to confirm patch effectiveness after the update; it also helps us for preparing audits such as iso 27001, and regulatory requirements, it also helps us to identify open ports and services that violate security.

• Lack of visibility of external assets
• Reduction of the risk of external attacks
• Falta de visibilidad de activos externos
• Reducción del riesgo de ataques externos

Incentivized

• Nessus is best at performing vulnerability scans, in fact, it gives findings and moreover accurate findings of the assessments. It does not do penetration testing or exploit the vulnerabilities because it is concerned about scanning the systems/applications.
• In fact, Nessus has multiple profiles/policies to perform different types of scans such as, scans oriented for PCI-DSS, malware scans, web application scans, bad shell shock detection scan to name a few.
• Nessus has the ability to classify the vulnerabilities into risk-based categories from critical to even informational which I think is one of the things that separates Nessus from other vulnerability scanners.

Incentivized

• Asset Attribution and Ownership Clarity
• Risk Prioritization and Business Context
• Noise and False Positives

Incentivized

• The tool has lots of options for setting up before scanning any device, this methodology could be simplified further with default configuration for various devices predefined, anyhow we can use this technique by making use of policies.
• For advanced users we cannot disable the plugins inside the plugin groups, we can enable the whole set of plugins at a time, for few hundreds its ok, but thousands of plugins are of waste of resource and time.

Incentivized

Nessus is best and easy to use application for Vulnerabilities finding and reporting, it has multiple platforms and wide scope covering almost all devices for security improvement so far, thus we are very likely to continue its services.

Incentivized

We rate Microsoft Defender External Attack Surface Management’s overall usability as 10 out of 10 because it delivers a strong balance between depth of capability and ease of use, particularly within organizations already operating in the Microsoft security ecosystem.

Incentivized

Tenable Nessus is a great product and provides a lot of value, but it is difficult to set up and use and the amount of data it generates can be overwhelming. It does help us prioritize based on the severity of the detection, however there are sometimes mitigating factors that we have implemented that Nessus does not account for, which causes lots of noise in the reports.

Incentivized

I haven't needed to contact support yet. But issues are easily solved with a quick internet search which means support and by extension, the larger community are involved and knowledgeable.

Incentivized

Because Microsoft Defender External Attack Surface Management is part of the broader Microsoft Defender family (including Defender XDR, Entra ID, Azure Security, Sentinel, etc.), it:
Shares identity, endpoint, and threat context across tools
Reduces the need for custom integrations or connectors
Works in a “single pane of glass” experience for SOC analysts
Why it matters:
Organizations already invested in Microsoft security tools gain greater contextual insight and lower operational overhead.

Incentivized

Sometimes when we identify a vulnerability with Nessus that has an exploit, we made a proof of concept with Metasploit in order to show to the IT managers the importance of the software/hardware hardening.

Incentivized

• Reduced Business Risk from Unknown External Assets
• Operational Efficiency and Cost Avoidance
• Faster Risk Identification During Change Events

Incentivized

• Nessus certainly has a positive impact while me while performing my job, either as security research, or performing vulnerability assessments for clients. It gives a lot of information about the system/application after performing scans. The number of false positives is also less compared to other vulnerability scanners.
• The professional edition is very useful as policy templates available in this edition are very handy and useful even to perform compliance scan like PCI DSS scan.
• Also, the ability to export the scan results into reports in formats like HTML, PDF is very useful which could be for performing system/application reviews.

Incentivized