Unsafe remote resource fetching in expansion misp-modules

MISP modules are autonomous modules that can be used to extend MISP for new services. Prior to 3.0.7, an unsafe remote resource fetching vulnerability existed in MISP Modules expansion modules. The html_to_markdown module accepted arbitrary HTTP(S) URLs without sufficient validation, which could allow Server-Side Request Forgery against loopback, private, or link-local network resources. Additionally, the qrcode module disabled TLS certificate verification when retrieving remote images, exposing requests to potential man-in-the-middle interception or response tampering. The issue was fixed by validating URL schemes, blocking local and private address ranges, resolving hostnames before fetching, enforcing request timeouts, and re-enabling TLS certificate verification. This vulnerability is fixed in 3.0.7.