Ensure that all application functionalities work correctly under the new PHP version. Why Upgrade to PHP 8.x?
Common vulnerability types affecting this branch include: php version 5640 vulnerabilities link
Search the NVD CVE Portal using the keyword "PHP 5.6.40" to view CVSS severity scores, technical breakdowns, and exploitability vectors. php version 5640 vulnerabilities link
Do you have a currently deployed in front of this server? php version 5640 vulnerabilities link