There are many functions built into php, with their help we can develop and maintain more quickly, but there are still many functions in this function that are accompanied by high risks, such as the 16 Don't use functions unless absolutely necessary, because many "experts" can exploit your vulnerabilities through these functions.
1. passthru()
Function description: Allows to execute an external program and echo the output, similar to exec().
Danger level: High
2. exec()
Function description: Allows the execution of an external program (such as UNIX Shell or CMD commands, etc.).
Danger level: High
3. system()
Function description: Allows the execution of an external program and echoes the output, similar to passthru( ).
Danger level: High
4.chroot()
Function description: Can change the working root directory of the current PHP process, only if the system supports it It can only work in CLI mode
PHP, and this function is not applicable to Windows systems.
Danger level: High
5. chgrp()
Function description: Change the user group to which a file or directory belongs.
Danger level: High
6. chown()
Function description: Change the owner of the file or directory.
Danger level: High
7. shell_exec()
Function description: Execute the command through the Shell and return the execution result as a string.
Danger level: High
8, proc_open()
Function description: Execute a command and open the file pointer for reading and writing .
Danger level: High
9. proc_get_status()
Function description: Get information about the process opened using proc_open().
Danger level: High
10. ini_alter()
Function description: It is an alias function of the ini_set() function, and its function is the same as ini_set() ) same.
See ini_set() for details.
Danger level: High
11. ini_set()
Function description: Can be used to modify and set PHP environment configuration parameters.
Danger level: High
12. ini_restore()
Function description: Can be used to restore PHP environment configuration parameters to their initial values.
Danger level: High
13. dl()
Function description: Load a PHP external modules.
Danger level: High
14. pfsockopen()
Function description: Establish a socket persistent connection in the Internet or UNIX domain.
Danger level: High
15. popen()
Function description: A command can be passed through the parameters of popen(), and popen() () to execute the file opened.
Danger level: High
16. putenv()
Function description: Used to change the system character set environment when PHP is running. In PHP versions earlier than 5.2.6, you can use this function
to modify the system character set environment, and then use the sendmail command to send special parameters to execute the system SHELL command.
Danger Level: High
The above is the detailed content of 16 high-risk functions in PHP. For more information, please follow other related articles on the PHP Chinese website!