What is the potential security issue indicated by the SecureSSI message in the PHP script?

The potential security issue indicated by the SecureSSI message in the PHP script is the use of Server Side Includes (SSI) which can allow for code injection attacks if not properly sanitized. To solve this issue, it is recommended to disable SSI or properly sanitize any user input before including it in the script.

// Disable Server Side Includes (SSI) in the PHP script
ini_set('engine', 'none');