---
id: "CVE-2026-128052"
page: "https://infrastack.ai/live/CVE-2026-128052"
kind: "vulnerability"
aliases: ["CVE-2026-128052"]
title: "OpenMage magento-lts: template filter lets admins render restricted layout blocks"
severity: "medium"
cvss: 5.1
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["magento-lts", "openmage", "package", "php", "self-hosted"]
not_affected_if: ["fixed-version", "no-untrusted-content-editors"]
published_at: "2026-11-13T10:18:11+00:00"
first_seen_at: "2026-11-13T10:47:33+00:00"
updated_at: "2026-11-13T10:58:35+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-128052", "first_seen_at": "2026-11-13T10:47:33+00:00"}]
exploit_sources: []
---

# OpenMage magento-lts: template filter lets admins render restricted layout blocks

Link for people: https://infrastack.ai/live/CVE-2026-128052 (this .md is for agents)

OpenMage magento-lts has an authorization gap in its template filter: the {{layout}} directive renders any layout handle without the admin/block whitelist that {{block}} enforces. An administrator who can edit email, CMS, widget or newsletter content can use it to render disallowed blocks and disclose limited information.

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

## How to check

- Confirm the installed version with `composer show magento-lts/magento-lts` or the version in your OpenMage install
- Check whether the installed version is below `20.19.0` on the 20.x line, or below `21.0.0-beta3` on the 21.0.0-beta line

## Fix

- Move to `20.19.0` on the 20.x line
- Move to `21.0.0-beta3` on the 21.0.0-beta line

## Timeline

- 2026-11-13T10:47:33+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-128052

## Documents

- [advisory] Vendor advisory: github.com https://github.com/OpenMage/magento-lts/security/advisories/GHSA-fqq6-76qg-2r96
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/openmage-magento-lts-before-20.19.0-block-whitelist-bypass-via-layout-directive
- [fix] Patch: github.com https://github.com/OpenMage/magento-lts/commit/055ccb866c0fadfed2c27e8c0e9ebd10db0199df

## From the sources

OpenMage magento-lts before 20.19.0 and 21.0.0-beta1 before 21.0.0-beta3 contains an incorrect authorization vulnerability in the template filter's {{layout}} directive, which renders arbitrary layout handles without enforcing the admin/block whitelist that the {{block}} directive applies. Administrators with rights to edit email, CMS, widget or newsletter content can embed {{layout}} with arbitrary handles to render disallowed blocks and disclose limited information.

---

_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_