PHP Remote Code Execution (RCE) via Global State Use-After-Free (CVE-2026-109619)

The primary remediation is to upgrade to a patched version of PHP.

1. Update via Package Manager (Example for RHEL/CentOS)

sudo yum update php

2. Restart Services

After updating, you must restart the PHP-FPM or Web Server service to apply the changes in memory.

sudo systemctl restart php-fpm
# Or for Apache
sudo systemctl restart httpd

3. Monitoring

Monitor for unusual segmentation faults in PHP logs, which may indicate failed exploitation attempts or memory corruption issues.

This vulnerability arises from a flaw in how PHP manages its global state across multiple requests. Specifically, certain global pointers may continue to reference memory that was allocated for a specific request even after that request has finished and the memory has been freed (Use-After-Free). Subsequent requests may then access or branch based on this stale, uninitialized, or attacker-controlled memory state. Due to the nature of PHP's memory management, this can be weaponized to achieve Remote Code Execution. The high EPSS score and CISA KEV status indicate that this is a critical threat actively targeted by attackers.