https://aboutdfir.com/education/challenges-ctfs/ (Contains types, details, writeups)
https://www.forensicfocus.com/challenges-and-images/ (Contains test images, example CTFs and writeups)
https://www.amanhardikar.com/mindmaps/ForensicChallenges.html (Mindmap of various events and challenges)
https://www.hecfblog.com/2019/04/daily-blog-657-mus2019-dfir-ctf-open-to.html (still playable - download file and register at site)
http://flare-on.com/ (https://2020.flare-on.com/) (still playable)
https://tryhackme.com/room/iosforensics (paid)
https://tryhackme.com/hacktivities -> search ‘forensics’ (paid)
https://cybertalents.com/challenges/forensics
http://forensicscontest.com/puzzles (Network Forensics)
https://github.com/stuxnet999/MemLabs
https://blog.bi0s.in/2020/08/04/Forensics/InvestigationContd-InCTFi20/ (writeup)
https://blog.bi0s.in/2020/08/04/Forensics/InCTFi-LOGarithm/ (writeup)
https://dfirmadness.com/the-stolen-szechuan-sauce/ (Highly Recommended)
https://digital-forensics.sans.org/community/challenges (Recommended)
https://betweentwodfirns.blogspot.com/2017/11/dfir-ctf-precision-widgets-of-north.html (Recommended)
https://medium.com/@ozan.unal/defcon-dfir-ctf-2019-writeup-38f168eda56b (writeup)
https://www.cfreds.nist.gov/ (Example Data Sets and Practice Files)
https://www.enisa.europa.eu/topics/trainings-for-cybersecurity-specialists/online-training-material/technical-operational (Training, Practice Files, Highly Recommended)