---
id: "CVE-2026-128020"
page: "https://infrastack.ai/live/CVE-2026-128020"
kind: "vulnerability"
aliases: ["CVE-2026-128020"]
title: "FrankenPHP: circular PHP arrays crash the whole server process"
severity: "high"
cvss: 8.2
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["frankenphp", "go", "php", "runtime", "self-hosted"]
not_affected_if: ["no-worker-mode", "patched-version"]
published_at: "2026-11-13T10:18:07+00:00"
first_seen_at: "2026-11-13T10:47:30+00:00"
updated_at: "2026-11-13T10:51:23+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-128020", "first_seen_at": "2026-11-13T10:47:30+00:00"}]
exploit_sources: []
---

# FrankenPHP: circular PHP arrays crash the whole server process

Link for people: https://infrastack.ai/live/CVE-2026-128020 (this .md is for agents)

FrankenPHP before 1.13.2 does not detect self-referential PHP arrays when converting them to Go values, so passing one to frankenphp_log() or returning one from a worker callback causes a fatal Go stack overflow. An attacker who can get such a request through terminates the entire server process, a denial of service.

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

## How to check

- Check the FrankenPHP version with `frankenphp version` or the binary your server runs
- Look for calls to `frankenphp_log()` and worker callbacks that return arrays built from user input

## Fix

- FrankenPHP: `1.13.2`

## Timeline

- 2026-11-13T10:47:30+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-128020

## Documents

- [advisory] Vendor advisory: github.com https://github.com/php/frankenphp/security/advisories/GHSA-ccgp-ch9h-533f
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/frankenphp-before-1.13.2-denial-of-service-via-cyclic-array-conversion

## From the sources

FrankenPHP before 1.13.2 contains an uncontrolled recursion vulnerability in its PHP-to-Go array converter that fails to detect circular references in PHP arrays. Passing a self-referential array to frankenphp_log() or returning one from a worker callback triggers a fatal Go stack overflow, terminating the entire server process.

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