Multiple vulnerabilities have been discovered in PHP, the most severe of which could allow an attacker to execute arbitrary code. Successfully exploiting the most severe of these vulnerabilities could allow for arbitrary code execution in the context of the affected application. 
Depending on the privileges associated with the application, an attacker could install programs; view, change, or delete data; or create new accounts with full user rights. Failed exploitation could result in a denial-of-service condition.
- PHP 7.1 prior to 7.1.12 
- PHP 7.0 prior to 7.0.26 
- Upgrade to the latest version of PHP immediately, after appropriate testing.
- Verify no unauthorized system modifications have occurred on system before applying patch.
- Apply the principle of Least Privilege to all systems and services.
- Remind users not to visit websites or follow links provided by unknown or untrusted sources.