"popen() has been disabled for security reasons" error

Symptoms

When trying to install a PHP extension using PECL, the following error appears:

Warning: popen() has been disabled for security reasons in PEAR/Builder.php on line 525
ERROR: failed to run `phpize'

Description

This error indicates that the popen() function is disabled in the global php.ini file for the affected PHP version.

[ root@server ~]# grep disable_functions /opt/cpanel/ea-php*/root/etc/php.ini
/opt/cpanel/ea-php56/root/etc/php.ini:disable_functions = show_source, system, shell_exec, passthru, exec, popen, proc_open
/opt/cpanel/ea-php70/root/etc/php.ini:disable_functions = show_source, system, shell_exec, passthru, exec, popen, proc_open
/opt/cpanel/ea-php71/root/etc/php.ini:disable_functions = show_source, system, shell_exec, passthru, exec, popen, proc_open
/opt/cpanel/ea-php72/root/etc/php.ini:disable_functions = show_source, system, shell_exec, passthru, exec, popen, proc_open
/opt/cpanel/ea-php73/root/etc/php.ini:disable_functions = show_source, system, shell_exec, passthru, exec, popen, proc_open
/opt/cpanel/ea-php74/root/etc/php.ini:disable_functions = show_source, system, shell_exec, passthru, exec, popen, proc_ope

The error can also indicate that popen() is disabled in either the domain's individual PHP-FPM configuration or in the global PHP-FPM configuration.

Workaround

If the domain uses ea-php, you'll need to remove popen() from the disable_functions variable within the global php.ini file.

There are several ways to accomplish this.

• Manually editing the global php.inifile of the affected version and removing popen() from the disable functions.

This global php.ini configuration is located in the following paths:

/opt/cpanel/ea-php56/root/etc/php.ini
/opt/cpanel/ea-php70/root/etc/php.ini
/opt/cpanel/ea-php71/root/etc/php.ini
/opt/cpanel/ea-php72/root/etc/php.ini
/opt/cpanel/ea-php73/root/etc/php.ini
/opt/cpanel/ea-php74/root/etc/php.ini

• "WHM / Software / MultiPHP INI Editor."

To do so, access "WHM  /Software / MultiPHP INI Editor." Once there select click on Editor Mode, select the version of PHP you'd like to edit. Search for disable_functions and then remove popen().

If the affected domain uses PHP-FPM, please refer to the following article, which explains how to disable the function: How to modify disable_functions in WHM when using PHP-FPM.