Server-Side Request Forgery (SSRF)
An issue was discovered in Simple Machines Forum (SMF) before release 2.0.17. There is SSRF related to Subs-Package.php and Subs.php because user-supplied data is used directly in curl calls.
CWE-918 - Server-Side Request Forgery (SSRF)
Server-side request forgery (SSRF) is a weakness that allows an attacker to send an arbitrary request, making it appear that the request was sent by the server. This request may bypass a firewall that would normally prevent direct access to the URL. The impact of this vulnerability can vary from unauthorized access to files and sensitive information to remote code execution.