The PHP development team has released security updates to address two critical remote code execution vulnerabilities in the popular server-side scripting language.
Both flaws, identified as CVE-2026-109618 and CVE-2026-109619, carry a CVSSv4.0 base score of 9.2 and are classified as Critical. The advisories were published on October 21, 2026 (UTC), following a preview announcement made the previous day.
Vulnerability Details
CVE-2026-109618 arises from incomplete initialization of request data when memory allocation fails. Processing is interrupted before initialization completes, allowing residual memory contents to be treated as valid data during cleanup routines, which can lead to arbitrary code execution.
CVE-2026-109619 involves leftover state information that persists after memory is freed at the end of a request. Subsequent requests handled by the same worker process can reference this stale data, potentially resulting in code execution.
The PHP team has strongly recommended that all users apply the latest security updates without delay to mitigate the risks.


