How to Contain PHP Trojan Attacks_PHP Tutorial

Everyone knows that surfing on the Internet must withstand viruses and Trojan attacks to protect our clean surfing environment. Here, you will learn about

1. Prevent jumping out of the web directory

To defend against PHP Trojan attacks, first modify httpd.conf. If You only allow your php script program to operate in the web directory, and you can also modify the httpd.conf file to limit the operation path of php. For example, if your web directory is /usr/local/apache/htdocs, then add these lines to httpd.conf:

php_admin_value open_basedir /usr/local/apache
/htdocs

In this way, if the script wants to read files other than /usr/local/apache/htdocs, it will not be allowed. If the error display is open, an error like this will be prompted:

Warning: open_basedir restriction in effect. File is in wrong directory in

/usr/local/apache/htdocs/open.php on line 4

etc.

2. Prevent PHP Trojan attacks from executing webshell

Open safe_mode, set in php.ini

disable_functions= passthru, exec, shell_exec, system

You can choose one of the two, or you can choose both

3. Prevent PHP Trojan attacks from reading and writing file directories

in php.ini disable_functions= passthru, exec, shell_exec, system followed by PHP file processing functions, mainly include:

fopen, mkdir, rmdir, chmod, unlink, dir

fopen, fread, fclose, fwrite, file_exists

closedir, is_dir, readdir.opendir

fileperms.copy, unlink, delfile

becomes

disable_functions= passthru, exec , shell_exec, system, fopen, mkdir, rmdir, chmod, unlink, dir

, fopen, fread, fclose, fwrite, file_exists

, closedir, is_dir, readdir.opendir

, fileperms.copy, unlink, delfile

ok, you’re done, the php Trojan can’t take us away. Unfortunately, in this case, those things that use text databases will not be usable.

If apache is built on a windos platform, we need to pay attention to one more thing. Apache runs with system permissions by default, which is scary and makes people feel uncomfortable. Then let’s lower the permissions of apache.

net user apache fuckmicrosoft /add

net localgroup users apache /del

ok. We created a user apche that does not belong to any group.

We open the computer manager, select services, click on the properties of the apache service, we select log on, select this account, we fill in the account and password created above, restart the apache service, ok, apache is running on Low authority.

In fact, we can also set the permissions of each folder so that the apache user can only perform what we want it to do, and create a separate read-write user for each directory. This is also a popular configuration method used by many virtual host providers. However, this defense method for PHP Trojan attacks is overkill when used to prevent it.