PHP FastCGI Process Manager (FPM) Buffer Overflow Vulnerability

In some versions of PHP in certain configurations of FPM setup, it is possible to cause FPM module to write past allocated buffers allowing the possibility of remote code execution.

Published 8 Sep 2026Updated 8 Sep 20265 sources
CVSS 9.8 ✓ VERIFIED REFERENCE△ CISA KEV

What happened

In some versions of PHP in certain configurations of FPM setup, it is possible to cause FPM module to write past allocated buffers allowing the possibility of remote code execution.

Affected versions

FastCGI Process Manager (FPM): See original advisory Fixed: See vendor advisory.

Why it matters

This source correlation may provide earlier visibility while structured CVE metadata is still being updated.

Detection & mitigation

  • Review the original advisory and validate affected versions.
  • Apply vendor-provided updates or mitigations when available.

Public PoC references