# Nessus

> free network vulnerability scanning tool

**Wikidata**: [Q1070329](https://www.wikidata.org/wiki/Q1070329)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Nessus_(software))  
**Source**: https://4ort.xyz/entity/nessus

## Summary
Nessus is a proprietary vulnerability scanner developed by Tenable Network Security. Originally released in 1998 as free software under the GNU General Public License, it transitioned to a proprietary license on October 5, 2005. The tool is designed to scan networks for security vulnerabilities and is compatible with Microsoft Windows and Unix-like operating systems.

## Key Facts
- **Classification:** Nessus is a vulnerability scanner used for network security.
- **Developer:** Developed by Tenable Network Security.
- **Licensing:** Originally free software (GNU GPL), it became proprietary software on October 5, 2005.
- **Initial Release:** The software was first published in 1998.
- **Operating Systems:** Runs on Microsoft Windows and Unix-like operating systems.
- **Current Status:** Classified as proprietary software and copyrighted.
- **Website:** hosted at tenable.com.
- **Aliases:** Also known as the Nessus Attack Scripting Language or 涅索斯.

## FAQs
### Q: Is Nessus free to use?
A: No, the current version is proprietary software. While it was originally released as free software under the GNU General Public License, it switched to a proprietary license on October 5, 2005.

### Q: What operating systems does Nessus support?
A: Nessus runs on Microsoft Windows and Unix-like operating systems.

### Q: Who develops Nessus?
A: Nessus is developed by Tenable Network Security.

### Q: When was Nessus first released?
A: The software was originally published in 1998.

## Why It Matters
Nessus serves as a critical tool in the cybersecurity industry for identifying network vulnerabilities. Its long history, dating back to 1998, marks it as a staple in security auditing, allowing organizations to detect potential security holes before they can be exploited. The software's evolution from a widely used open-source project to a commercial proprietary product reflects broader trends in the software industry where successful open-source tools eventually seek sustainable revenue models. By automating the process of monitoring network security, Nessus plays a significant role in the daily operations of security professionals, ensuring compliance and protecting digital infrastructure. Its compatibility with both Windows and Unix-like systems ensures it can be deployed in diverse IT environments.

## Notable For
- **Licensing Transition:** distinct history of moving from a free, open-source GNU General Public License to a closed, proprietary model in 2005.
- **Longevity:** has been in active development and use since its publication in 1998.
- **Cross-Platform Capability:** supports both Microsoft Windows and Unix-like architectures.
- **Industry Standard:** widely recognized and utilized within the information security sector for vulnerability management.

## Body

### Licensing and History
Nessus was initially published in 1998 as free software. It operated under the GNU General Public License until October 5, 2005. On this date, the licensing model shifted to a proprietary license. Consequently, the "instance of" classification for the software changed from "free software" to "proprietary software." The software is currently copyrighted.

### Developer and Ownership
The software is developed and maintained by Tenable Network Security. The developer relationship with Tenable Network Security is noted specifically starting from the licensing transition date in 2005.

### Platform Compatibility
Nessus is designed to operate across different computing environments. It is compatible with:
-   **Microsoft Windows:** The family of computer operating systems developed by Microsoft.
-   **Unix-like operating systems:** Operating systems that behave in a manner similar to a Unix system.

### Version History
The software has undergone numerous updates and version iterations. Key release dates and versions include:
-   **1998:** Initial publication.
-   **2005-10-05:** Release of version 3.0 and license change.
-   **2009-04-09:** Release of version 4.0.0.
-   **2012-02-15:** Release of version 5.0.
-   **2014-03-24:** Stable release of version 5.2.6.
-   **2014-10-14:** Release of version 6.0.
-   **2017-12-12:** Release of version 7.0.0.
-   **2018-12-04:** Release of version 8.1.
-   **2019-05-14:** Release of version 8.4.0.

### Technical Identifiers
The software is identified by various technical tags and directories, including the ArchWiki article "Nessus," the Gentoo package `net-analyzer/nessus-bin`, and the Repology project name `nessus`. It is also listed under the SIC code 7372 for Prepackaged Software.

## References

1. [Nessus 5.2.6 Is Available for Download. 2014](http://www.tenable.com/blog/nessus-526-is-available-for-download)
2. [Source](https://community.tenable.com/thread/1267)
3. [Source](https://community.tenable.com/thread/4266)
4. [Source](http://static.tenable.com/prod_docs/upgrade_nessus.html)
5. [Source](https://docs.tenable.com/releasenotes/nessus/nessus64.htm)
6. [Source](https://docs.tenable.com/releasenotes/nessus/)
7. [Source](https://docs.tenable.com/releasenotes/Content/nessus/nessus8120.htm)
8. [Nessus 10.0.2 Release Notes - 2021-12-14. 2021](https://docs.tenable.com/releasenotes/Content/nessus/nessus1002.htm)
9. [Nessus 10.1.1 Release Notes. 2022](https://docs.tenable.com/releasenotes/Content/nessus/nessus1011.htm)
10. [Tenable EOL Release Notes. 2025](https://docs.tenable.com/pdfs/EOL/Tenable_EOL_Release_Notes.pdf#%5B%7B%22num%22%3A723%2C%22gen%22%3A0%7D%2C%7B%22name%22%3A%22XYZ%22%7D%2C43.5%2C471%2C0%5D)
11. [Tenable Nessus 10.9.1 (2025-07-09). 2025](https://docs.tenable.com/release-notes/Content/nessus/2025.htm#TenableNessus109120250709)
12. Freebase Data Dumps. 2013