---
id: CVE-2026-82416
title: FrankenPHP is a modern application server for PHP
summary: >-
  FrankenPHP is a modern application server for PHP. Prior to 1.12.5, FrankenPHP
  worker mode can retain PHP session state between requests when the session
  extension is loaded as a shared module and is unavailable through
  HAVE_PHP_SESSION …
severity: high
cvss: 7.7
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L'
cwe:
  - CWE-362
  - CWE-488
published: '2026-10-13'
updated: '2026-10-13'
sourceUpdated: '2026-10-13T21:18:22.463'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-82416'
references:
  - url: >-
      https://github.com/php/frankenphp/commit/be24d82531675f90862b8cde1e9fc7e9ee855aa5
    label: security-advisories@github.com
  - url: 'https://github.com/php/frankenphp/pull/2523'
    label: security-advisories@github.com
  - url: 'https://github.com/php/frankenphp/releases/tag/caddy/v1.12.5'
    label: security-advisories@github.com
  - url: 'https://github.com/php/frankenphp/security/advisories/GHSA-v3ph-cgqh-r8p5'
    label: security-advisories@github.com
tags:
  - nvd
ingestedAt: '2026-10-13T17:38:53.199Z'
---

## Overview

FrankenPHP is a modern application server for PHP. Prior to 1.12.5, FrankenPHP worker mode can retain PHP session state between requests when the session extension is loaded as a shared module and is unavailable through HAVE_PHP_SESSION at compile time. In this build configuration, frankenphp_reset_session_state() is compiled out, PS(id) can survive a request boundary, and a subsequent session_start() can ignore the new request's cookie because an identifier is already present. Under concurrent requests, session_id() can therefore return another client's identifier or a stale identifier from a previous request on the same worker thread, causing cross-user session exposure, possible session hijacking, and intermittent logout behavior. Builds with the session extension statically linked, including the official static binaries and Docker images, are not affected. This issue is fixed in version 1.12.5.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.