---
id: "CVE-2026-128018"
page: "https://infrastack.ai/live/CVE-2026-128018"
kind: "vulnerability"
aliases: ["CVE-2026-128018"]
title: "FrankenPHP: fatal startup error in worker mode leaves requests hanging forever"
severity: "medium"
cvss: 6.3
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["frankenphp", "php", "runtime", "self-hosted", "worker-mode"]
not_affected_if: ["default-config", "no-worker-mode"]
published_at: "2026-11-13T10:18:07+00:00"
first_seen_at: "2026-11-13T10:47:30+00:00"
updated_at: "2026-11-13T10:55:15+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-128018", "first_seen_at": "2026-11-13T10:47:30+00:00"}]
exploit_sources: []
---

# FrankenPHP: fatal startup error in worker mode leaves requests hanging forever

Link for people: https://infrastack.ai/live/CVE-2026-128018 (this .md is for agents)

FrankenPHP before 1.13.4 can leave a client request unfinished when a worker script hits a fatal error during request startup, because frankenphp_handle_request() returns false without completing the dequeued request. An attacker who triggers those startup fatals can make client requests hang indefinitely while the worker keeps running.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the FrankenPHP version in use, for example with `frankenphp version`.
- Look for worker mode in the Caddyfile or config, for example `php_server` with a `worker` directive.

## Fix

- FrankenPHP: move to `1.13.4` or later.

## Timeline

- 2026-11-13T10:47:30+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-128018

## Documents

- [advisory] Vendor advisory: github.com https://github.com/php/frankenphp/security/advisories/GHSA-x6j6-qv7w-fq3c
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/frankenphp-before-1.13.4-pending-worker-request-denial-of-service
- [fix] Patch: github.com https://github.com/php/frankenphp/commit/185bfe578af854d29d7bdff3dd83b3b9dea3572b

## From the sources

FrankenPHP before 1.13.4 contains a denial of service vulnerability in worker mode where frankenphp_handle_request() returns false without finishing the dequeued request after a fatal error during request startup. Attackers who trigger startup fatal errors against worker scripts that keep calling frankenphp_handle_request() can leave client requests hanging indefinitely while the worker continues running.

---

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