Having trouble downloading Nessus to your computer or virtual machine? Do you see the error: “Failed to download Nessus. An unexpected error occurred while downloading plugins?”
Well, you’re in luck! You can easily fix this error in no time and start scanning for vulnerabilities with Nessus on your Linux machine. Here’s how.
What is Nessus?
Nessus is an open-source vulnerability scanner developed by Tenable Inc. It provides a subscription service for security engineers, penetration testers, and other cybersecurity personnel and enthusiasts to proactively find network vulnerabilities, identify and correct them, and automate analyses.
Nessus has a paid subscription, Nessus Professional, and a free version, Nessus Essentials, limited to just 16 IP addresses per scanner. Nessus offers various services such as Vulnerability Assessment, Vulnerability Scan, Network Scan, Web Scan, Asset Discovery, etc.
What could cause the “Nessus Download Failed” error?
As indicated in the error message provided by Nessus when the download fails, network issues, lack of disk space, or proxy filtering are causing the error.
When downloading the Nessus service, make sure you have a stable internet connection. If your device is not connected to a stable network or if the internet went down while you were downloading Nessus, the download will fail. Check out these tips to improve your internet speed and connectivity.
Before troubleshooting this issue, try the following:
Toggle the airplane mode button on and off to reset the internet connection.
If you’re using a Wi-Fi router, turn it off and then back on. Then make sure it is in a raised position.
Check your connection speed and make sure it doesn’t fluctuate.
Insufficient disk space
Does your computer have enough disk space to download Nessus plug-ins and components? Be sure to delete or move some files to make room for new ones.
Chances are you are running Linux in a virtual machine such as VMware, VirtualBox, HyperV, etc. Change your Linux virtual machine settings and increase allocated storage. Or you can free up disk space on your Linux computer with these GUI tools.
Your proxy server may be preventing the Nessus service from updating or downloading your plugins. Make sure “plugins.nessus.org” is not filtered by slow proxy servers or proxy-based antivirus. Configure your proxy server to allow or disable this service.
How to Fix “Nessus Download Failed” Error
This is a common error that occurs when trying to download Nessus on your computer. It usually says: Nessus Download Failed. An unexpected error occurred while downloading plugins.
This could be due to a network error, lack of disk space, or something else. Please take one of the following corrective actions:
Run the command “nessuscli update”
Nessus download fails because plugins do not install completely or install at all. When this happens, Nessus returns minimal or sometimes empty scans when you use it to scan for vulnerabilities.
Here’s how to fix the error:
Open your Linux terminal and stop the Nessus service.
Update all plugins using the nessuscli update ordered.
/opt/nessus/sbin/nessuscli update --all
Restart the Nessus service once the plugins download is complete.
The commands to start and stop the service may be different depending on the distribution you are using.
You will now be able to use the Nessus service without any hindrance.
Vulnerability scanning with Nessus on Linux
Now that you have fixed the error, you can move on to scanning for vulnerabilities with Nessus. Feel free to take advantage of the many templates and tools made available by Nessus to ensure that there are no vulnerabilities that could lead to serious cyber threats.
What is vulnerability scanning and how does it work?
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