There is [vulnhub](https://www.vulnhub.com/). There was another one that started with an “e” (it had Linux and code challenges too (e.g. here is the C code, exploit privilege escalation)). I remember a few years ago the site went down and a mirror was stood up under a different domain. Don’t have those links unfortunately.
Edit. Found it:
- What it used to be: https://web.archive.org/web/20180202211058/https://exploit-e...
- Mirror: https://exploit.education/
- Also can be downloaded at vulnhub: https://www.vulnhub.com/series/exploit-exercises,11/