In 2024, PHP underwent its first external security audit in years. The PHP Foundation secured funding from the Sovereign Tech Agency to organize this audit through OSTIF, and it was carried out by Quarkslab. While fixing one of the issues Quarkslab reported, a PHP core developer contracted by the PHP Foundation found the first signs of the OOM problem behind CVE-2026-109618. In 2024, a potential exploit for the OOM problem was theorized, but no concrete vectors were found and other concrete issues with clear impact overshadowed these concerns.

PHP 8.5.12, 8.4.27, 8.3.36 and 8.2.35 fix two critical vulnerabilities that can allow unauthenticated remote code execution. All PHP users are strongly encouraged to update immediately.