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@@ -471,7 +471,6 @@ See also [awesome-pcaptools](https://github.com/caesar0301/awesome-pcaptools).
 
 ### Online Penetration Testing Resources
 
-* [InfoSec Institute](https://resources.infosecinstitute.com) - IT and security articles.
 * [MITRE's Adversarial Tactics, Techniques & Common Knowledge (ATT&CK)](https://attack.mitre.org/) - Curated knowledge base and model for cyber adversary behavior.
 * [Metasploit Unleashed](https://www.offensive-security.com/metasploit-unleashed/) - Free Offensive Security Metasploit course.
 * [Open Web Application Security Project (OWASP)](https://www.owasp.org/index.php/Main_Page) - Worldwide not-for-profit charitable organization focused on improving the security of especially Web-based and Application-layer software.
@@ -498,7 +497,6 @@ See also [awesome-pcaptools](https://github.com/caesar0301/awesome-pcaptools).
 * [Honeypots](https://github.com/paralax/awesome-honeypots) - Honeypots, tools, components, and more.
 * [InfoSec § Hacking challenges](https://github.com/AnarchoTechNYC/meta/wiki/InfoSec#hacking-challenges) - Comprehensive directory of CTFs, wargames, hacking challenge websites, pentest practice lab exercises, and more.
 * [Infosec](https://github.com/onlurking/awesome-infosec) - Information security resources for pentesting, forensics, and more.
-* [Security-related Operating Systems](https://list.rawsec.ml/operating_systems.html) - List of security related operating systems.
 * [JavaScript Programming](https://github.com/sorrycc/awesome-javascript) - In-browser development and scripting.
 * [Kali Linux Tools](http://tools.kali.org/tools-listing) - List of tools present in Kali Linux.
 * [Node.js Programming by @sindresorhus](https://github.com/sindresorhus/awesome-nodejs) - Curated list of delightful Node.js packages and resources.
@@ -598,7 +596,6 @@ See also [awesome-osint](https://github.com/jivoi/awesome-osint).
 * [Android Tamer](https://androidtamer.com/) - Distribution built for Android security professionals that includes tools required for Android security testing.
 * [ArchStrike](https://archstrike.org/) - Arch GNU/Linux repository for security professionals and enthusiasts.
 * [AttifyOS](https://github.com/adi0x90/attifyos) - GNU/Linux distribution focused on tools useful during Internet of Things (IoT) security assessments.
-* [BackBox](https://backbox.org/) - Ubuntu-based distribution for penetration tests and security assessments.
 * [BlackArch](https://www.blackarch.org/) - Arch GNU/Linux-based distribution for penetration testers and security researchers.
 * [Buscador](https://inteltechniques.com/buscador/) - GNU/Linux virtual machine that is pre-configured for online investigators.
 * [Kali](https://www.kali.org/) - Rolling Debian-based GNU/Linux distribution designed for penetration testing and digital forensics.