Upcoming Critical PHP Security Release
Unrated
The PHP security team would like to give advance notice of an upcoming security release . It is scheduled for Wednesday, 21 October 2026 at 14:00 UTC. It addresses two critical vulnerabilities, both rated CVSS v4.0 9.2. All PHP users are encouraged to prepare now so they can upgrade as soon as the release is available. We reserve the right to release earlier should details of either vulnerability become public, or should evidence of active exploitation appear in the wild. Full details, affected versions, and the fixed versions will be published with the release.
Remediation
Update PHP to the fixed release for your branch (8.2.35, 8.3.36, 8.4.27, 8.5.12). Branches below 8.2 have no fixed release — upgrade the branch or take the site offline.
Affected PHP branches
See the source advisory.
Source: PHP.net News · retrieved 2026-10-22T10:19:14-04:00 · https://www.php.net/index.php#2026-10-20-1