---
id: "CVE-2026-116900"
kind: "vulnerability"
aliases: ["CVE-2026-116900"]
title: "REDAXO CMS: stored XSS in media and link widgets hijacks admin sessions"
severity: "medium"
cvss: 5.4
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["package", "php", "redaxo", "self-hosted"]
not_affected_if: ["no-untrusted-editors", "patched-version"]
published_at: "2026-10-27T11:17:33+00:00"
first_seen_at: "2026-10-27T11:31:28+00:00"
updated_at: "2026-10-27T11:32:10+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-116900", "first_seen_at": "2026-10-27T11:31:28+00:00"}]
---

# REDAXO CMS: stored XSS in media and link widgets hijacks admin sessions

REDAXO versions before 5.21.4 do not escape values rendered by the media, medialist, link and linklist widgets. A content editor can store crafted REX_INPUT_MEDIA or REX_INPUT_LINK values that break out of the value attribute and run script in administrators' backend sessions, which can be used to take over accounts.

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

## How to check

- Check the installed REDAXO version in the backend or in `redaxo/src/core/boot.php` and confirm whether it is below `5.21.4`
- Review which accounts have editor rights that can edit module or article content using the media and link widgets

## Fix

- Upgrade REDAXO to `5.21.4` or later
- Until upgraded, restrict content editor accounts to trusted users and review stored media and link values for script-like markup

## Timeline

- 2026-10-27T11:31:28+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-116900

## From the sources

REDAXO before 5.21.4 contains a stored cross-site scripting vulnerability that allows content editors to inject HTML by storing unescaped values rendered by media, medialist, link and linklist widgets. Attackers can submit crafted REX_INPUT_MEDIA or REX_INPUT_LINK values that break out of the value attribute, executing script in administrators' backend sessions to hijack accounts.

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