---
id: "CVE-2026-128046"
page: "https://infrastack.ai/live/CVE-2026-128046"
kind: "vulnerability"
aliases: ["CVE-2026-128046"]
title: "OpenMage magento-lts: unauthenticated file upload lets attackers run PHP code"
severity: "critical"
cvss: 9.2
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["ecommerce", "magento-lts", "openmage", "package", "php", "self-hosted"]
not_affected_if: ["fixed-version", "no-file-custom-options", "phar-not-executed"]
published_at: "2026-11-13T10:18:10+00:00"
first_seen_at: "2026-11-13T10:47:32+00:00"
updated_at: "2026-11-13T10:48:29+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-128046", "first_seen_at": "2026-11-13T10:47:32+00:00"}]
exploit_sources: []
---

# OpenMage magento-lts: unauthenticated file upload lets attackers run PHP code

Link for people: https://infrastack.ai/live/CVE-2026-128046 (this .md is for agents)

OpenMage magento-lts 20.17.0 before 20.18.2 and 21.0.0-beta1 before 21.0.0-beta3 blocks some PHP file extensions for uploads but omits phar, php8 and phps. An unauthenticated attacker can upload a .phar file through a product File custom option and request it directly to run code on the server.

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

## How to check

- Check the installed magento-lts version in composer.json or the release tag, and see whether it is below `20.18.2` (20.x line) or below `21.0.0-beta3` (21.0.0-beta line).
- Look at `general/file/protected_extensions` in the admin configuration to see whether `phar`, `php8` and `phps` are missing from the blocklist.
- Check whether the web server maps `.phar` to PHP and serves `media/custom_options`.

## Fix

- OpenMage magento-lts 20.x: upgrade to `20.18.2`
- OpenMage magento-lts 21.0.0-beta: upgrade to `21.0.0-beta3`

## Timeline

- 2026-11-13T10:47:32+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-128046

## Documents

- [advisory] Vendor advisory: github.com https://github.com/OpenMage/magento-lts/security/advisories/GHSA-4fxg-469f-r6fc
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/openmage-magento-lts-20.17.0-before-20.18.2-unrestricted-file-upload-rce-via-custom-options
- [fix] Patch: github.com https://github.com/OpenMage/magento-lts/commit/5b6f985785245a964aa3dc78609f6af44d9d5e27
- [fix] Patch: github.com https://github.com/OpenMage/magento-lts/commit/ba76b2346fe1e380f39c23e68ccb818d7324d24f
- [fix] Patch: github.com https://github.com/OpenMage/magento-lts/commit/dd692b825ba50f196bcc20ae67fbed48dd95da56

## From the sources

OpenMage magento-lts 20.17.0 before 20.18.2 and 21.0.0-beta1 before 21.0.0-beta3 contains an unrestricted file upload vulnerability because the general/file/protected_extensions blocklist omits phar, php8, and phps. Unauthenticated attackers can upload a .phar file through a product File custom option to a predictable media/custom_options path and request it directly to execute code on servers that map .phar to PHP and serve that directory.

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