I have identified the following CTF labs which are 24/7 and most if not all are free:
* Immersive Labs: https://immersivelabs.online
* pwnable.xyz (good for people new to CTF): https://pwnable.xyz/
* 365 CSAW: https://365.csaw.io
* CTF101: https://ctf101.org/
* Shellter Hacking Express: https://shellterlabs.com/en/contests/
* Backdoor: https://backdoor.sdslabs.co/
* ShellWePlayAGame?: https://shellweplayagame.org/
* RootMe: https://www.root-me.org/?lang=en
* OverTheWire: https://overthewire.org/wargames/
* Virginia Cyber Range: https://portal.virginiacyberrange.net/
* Hack The Box: https://www.hackthebox.eu/
* FuzzyLand: https://fuzzy.land/
* Hacking Lab: https://www.hacking-lab.com/index.html
To everyone that made me aware of these thank you!
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