What are the implications of using deprecated PHP functions in terms of security vulnerabilities?

Using deprecated PHP functions can lead to security vulnerabilities because these functions are no longer actively maintained or updated by the PHP community, making them more susceptible to exploitation by attackers. To address this issue, it is important to replace deprecated functions with their modern equivalents to ensure that your code is secure and up-to-date.

// Deprecated function
$deprecatedResult = mysql_query($query);

// Updated function
$updatedResult = mysqli_query($connection, $query);