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Local Root Vulnerability in PHP-FPM: Critical Vulnerability CVE-2021-21703

A critical vulnerability CVE-2021-21703 has been identified in PHP-FPM, the FastCGI process manager included in the main PHP distribution since branch 5.3 , which allows an unprivileged hosting user to execute code as root. The problem manifests itself on servers that use PHP-FPM, usually used in conjunction with Nginx, to organize the launch of PHP scripts. The researchers who identified the problem were able to prepare a working prototype of the exploit.