RFI

in regards to RFI, it can be exploited if the vulnerable function allows the inclusion of remote URLs. the benefit of this are:

1. enumerating local-only ports & webapps (e.g., SSRF)

2. gaining RCE by including a malicious script hosted by the attacker

WEBAPP FUNCTIONS ALLOWING RFI

any RFI vulnerability is also an LFI vulnerability as any function that allows remote URLs may also allow local files disclosure. However, the reverse may not necessarily be an RFI due to:

1. the vulnerable function may not allow including remote URLs

2. attackers may only control a portion of the filename & not the entire protocol wrapper (e.g., http://, ftp://, and https://)

3. the configuration may prevent RFI altogether, as most modern web servers disable including remote files by default

4. functions that do allow remote URLs may not necessarily allow code execution