Which functions in php cannot execute system commands

The functions in PHP that cannot execute system commands include: exec()system()passthru()shell_exec(). The reason is that these functions have security vulnerabilities, allowing malicious attackers to execute arbitrary commands. In order to execute system commands safely, PHP provides functions such as escapeshellarg() and escapeshellcmd(), as well as third-party extensions. When using system commands, you should follow best security practices, such as limiting the types of executable commands and monitoring system logs.

Functions in PHP that cannot execute system commands

PHP is a server-side scripting language that is widely used in Web development. In order to improve security, there are some functions in PHP that cannot execute system commands.

PHP function that cannot execute system commands:

• exec()
• system()
• passthru()
• shell_exec()
• proc_open() (only In safe mode)

Cause:

These functions allow scripts to execute system commands, which may lead to security vulnerabilities. For example, a malicious attacker could use these functions to execute arbitrary commands and gain control of the server.

How to safely execute system commands

Although the above functions cannot directly execute system commands, PHP still provides safe methods to execute system commands, such as:

• escapeshellarg(): Escape parameters to prevent command injection vulnerabilities.
• escapeshellcmd(): Escape commands to prevent command injection vulnerabilities.
• exec(): Use the disable_functions configuration directive to disable it and use it in a controlled environment.
• proc_open(): Use in safe mode and limit the types of executable commands.
• PHP Extensions: Install third-party extensions such as exec() to provide controlled execution of system commands.

Note:

When executing system commands, you should always follow best security practices, such as:

• Restrict what can be Types of executed commands
• Restrict user privileges for scripts
• Validate all input
  * Monitor system logs to detect anomalous behavior

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