How to use php in one sentence

In the new era of Internet information transmission, every website needs to ensure its own security to avoid hacker attacks. The one-sentence Trojan has become one of the common tools used by hackers to attack websites, and the most commonly used one is the PHP one-sentence Trojan. So, how to use php in one sentence?

1. The definition of PHP one-sentence Trojan

The PHP one-sentence Trojan refers to a malicious script written in PHP language. Its main purpose is to provide hackers with a way to remotely control the backend of the website. . Using a one-sentence Trojan, you can not only obtain the permissions of the website server, but also manipulate all the files and data of the website at will.

2. The composition of the php one-sentence Trojan

The code of the php one-sentence Trojan can be completed with an echo statement. The code is similar to:

echo @eval($_POST['php']);
?>

$_POST['php'] refers to sending the executed php script code to the Trojan through http post method executed in the program.

3. How to use php one-sentence Trojan

1. Use the characteristics of php to add one-sentence Trojan code in the php file:

< ?php echo @eval($_POST['php']); ?>

Note: The echo statement will not output anything.

2. Manually upload Trojan files to the website server
3. Use tools to upload one-sentence Trojans

Hackers can use tools to upload one-sentence Trojans to the target server. For example, upload an image file through the file upload function, and then change the file suffix to php.

4. Methods to prevent PHP one-sentence Trojans

1. Update the PHP version in a timely manner and patch PHP vulnerabilities;
2. Prohibit users from using PHP code when uploading files, and Review all files uploaded by users;
3. Comprehensive reinforcement of website security, including database anti-injection, anti-cross-site scripting attacks, etc.

In short, PHP one sentence Trojan is one of the common means used by hackers to attack websites. Website administrators should do a good job in strengthening website security, update patches in a timely manner, and check code vulnerabilities to ensure the security of the website. .

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