Only the latest tagged release is supported with security fixes.
This module is for development and integration environments, and it fetches from a host an administrator configures. Point it at an upstream you trust: it follows redirects (capped at 3, http and https only), so a hostile upstream could redirect a fetch at an internal address and have the response written into a publicly readable media directory.
Please do not open a public GitHub issue for security vulnerabilities.
Instead, report it privately via GitHub Security Advisories.
You should get a response within a few days. Once confirmed, a fix will be released and the advisory published with credit (unless you prefer to stay anonymous).