Microsoft Defender for Cloud Apps vs. Tenable Nessus

Microsoft Defender for Cloud Apps is well suited when working with other Microsoft Applications. For example, if you are working with Microsoft Office 365 it works very well when implementing CASB features. It works when implementing monitoring or blocks on Sanctioned applications however customizing the message to users is not that great.

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.

• The integration to Microsoft Entra ID is seamless, which allows Conditional Access to redirect the session to Microsoft Defender for Cloud App for it to take actions (Block or Monitor).
• Tracker users' activity is very good when troubleshooting or running an investigate.
• Detecting risky users through tight integration with Microsoft Entra ID is a very good feature.
• Detecting mass downloads and blocking the download of files from non-manage company devices is a very good feature as well.

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

• It takes some time to scan and apply the policies when there is some sensitive information.
• After it applies the policies, it works, but there is a delay.
• It doesn't provide any way to scan Microsoft Teams when an external exchange of images is happening. You can always do the filtering on the documents during the chat, but if there is an image, then some kind of OCR capability is required to detect it. At present, there is no way [Microsoft Cloud App Security] can go and detect those kinds of images and alert us

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

The interface is pretty simple and easy to use; however, you will need to do a lot of investigative research on your own to get comfortable with it. Originally, many of the Microsoft security tools had their own seperate consoles. Overtime, they have blended into one interface which is the ideal state. In some cases it is clear Microsoft had to pick which console a certain feature or setting was going to reside in and this leads to some confusion. For example, DLP is managed through Defender for Cloud Apps but you will also need to jump into Purview. For things like reverse proxy on your M365 tenant, you will need to go into Azure and setup conditional access rules. Not a big problem and I can understand why the settings are located where they are but for someone just starting out with Defender for Cloud Apps, it will take some time to figure out.

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 have not utilized actual support but the Sales and Product teams have been super helpful in moving our implementation forward and showing us the best practices.

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

More flexible and more features with easy integration with cloud services like Microsoft Azure and other cloud services. Overall both gives similar features but we prefer Microsoft cloud app security due to its high threat detection rate. mostly we have been able to stop the threat in very very less time.

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

• Cloud App Security saves us thousands of dollars finding and rectifying apps security issues
• Identity Security Posture helps the organization identity stay in shape, saving thousands of dollars on security consultations
• The cost of suffering a breach cannot be quantified, CAS helps minimize the chances of the attackers succeeding, with excellent historical logging for most operations

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