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. As reported by Bilal Teke.
Exploitability
AV:AAC:LAT:PPR:NUI:NVulnerable System
VC:LVI:NVA:NSubsequent System
SC:HSI:HSA:H5.8/CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:H/SI:H/SA:H