Use FastCGI in PHP to Parse Vulnerabilities and fix them _ php instances

This article describes how to use FastCGI in PHP to Parse Vulnerabilities and fix the vulnerabilities. For more information, see Vulnerability description:

Nginx supports PHP parsing in CGI Mode by default. The common practice is to set SCRIPT_FILENAME through regular expression matching in the Nginx configuration file. When you access the URL http: // 192.168.1.102/phpinfo.jpg/1.php, $fastcgi_script_namewill be set to “phpinfo.jpg/1. php "and constructed as SCRIPT_FILENAME and passed to php cgi. Pipeline is parsed as the PHP file.

Hazards:

Improper configuration of WebServer Fastcgi may cause other files (such as css, js, jpg and other static files) to be parsed and executed as php scripts. When a user uploads a malicious script webshell to a static file and passes it to the backend php for parsing and execution, attackers can gain operation permissions on the server.

Solution:

(For Nginx users, you can select solution 1 or solution 2. For IIS users, use solution 1)

Solution 1: Modify the php. ini file and set cgi. fix_pathinfo to 0. Restart PHP and NGINX (IIS ).

Solution 2: Add the following code to the Nginx configuration file:

The Code is as follows:

If ($ fastcgi_script_name ~ \ .. * \/. * Php ){
Return 403;
}

This line of code is equivalent to the 403 error code when the URL of test.jpg/a. php is matched. Restart Nginx after modification.