CVE-2025-66026: Redaxo/source Cross-Site Scripting Vulnerability

MODERATE
Advisory Identifier: GHSA-x6vr-q3vf-vqgq
Share
CVSS 6.1
CWE-79
Published
Advisory Summary

CVE-2025-66026 is a MODERATE (CVSS 6.1) cross-site scripting vulnerability (CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) affecting Redaxo/source libraries in the Packagist ecosystem. The issue involves redaxo cms is vulnerable to reflected xss in mediapool info banner via args[types]. Remediation is available by upgrading affected packages to version 5.20.1.

CVE-2025-66026 at a Glance

CVE Identifier CVE-2025-66026
GHSA Identifier GHSA-x6vr-q3vf-vqgq
Severity MODERATE
CVSS v3.1 Base Score 6.1
CWE Classification CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Product Redaxo/source
Package Ecosystem Packagist
Published Date
Last Updated

Security Impact

CVSS: 6.1

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction Required (UI:R)
Scope Changed (S:C)
Confidentiality Low (C:L)
Integrity Low (I:L)
Availability None (A:N)

How to Fix CVE-2025-66026

To remediate this vulnerability, upgrade all affected Redaxo/source dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

redaxo/source fixed: 5.20.1 
Upgrade redaxo/source to 5.20.1
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for redaxo/source

How to Check if You Are Affected

To determine whether your application is affected by CVE-2025-66026, inspect your project dependencies for Redaxo/source:

inspect dependencies for redaxo/source

Analyze the terminal output to locate any version of Redaxo/source in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 5.20.1), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'), where the product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. In Redaxo/source, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Summary A reflected Cross-Site Scripting (XSS) vulnerability exists in the Mediapool view where the request parameter `args[types]` is rendered into an info banner without HTML-escaping. This allows arbitrary JavaScript execution in the backend context when an authenticated user visits a crafted link while logged in. ### Details Control Flow: 1. `redaxo/src/addons/mediapool/pages/index.php` reads args via `rex_request('args', 'array')` and passes them through as `$argUrl` to `media.list.php`. 2. `redaxo/src/addons/mediapool/pages/media.list.php` injects `$argUrl['args']['types']` into an HTML string without escaping: ``` if (!empty($argUrl['args']['types'])) { echo rex_view::info(rex_i18n::msg('pool_file_filter') . ' <code>' . $argUrl['args']['types'] . '</code>'); } ``` ### PoC 1. Log into the REDAXO backend. 2. While authenticated, open a crafted URL like: `<host>/index.php?page=mediapool/media&args[types]="><img+src%3Dx+onerror%3Dalert%28document.domain%29>` 4. The info banner displays the unescaped value and activates the injected onerror handler, which opens an alert pop-up. ### Impact Arbitrary JavaScript execution in the backend, enabling theft of session cookies, CSRF tokens, or other sensitive data, and allowing an attacker to perform any administrative actions on behalf of the affected user.

CVE-2025-66026 Affected Redaxo/source Versions

1 component(s)
Fixed Versions:
5.20.1
Product / Package Ecosystem Affected Versions Fixed Version
redaxo/source
 Packagist
< 5.20.1
5.20.1

References

GitHub Advisory / Wiki ADVISORY
https://github.com/redaxo/redaxo/security/advisories/GHSA-x6vr-q3vf-vqgq
NVD — CVE-2025-66026 NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-66026
Security Fix Commit FIX COMMIT
https://github.com/redaxo/redaxo/commit/58929062312cf03e344ab04067a365e6b6ee66aa
Redaxo/source Source Repository REPOSITORY
https://github.com/redaxo/redaxo

Frequently Asked Questions

What is CVE-2025-66026?
CVE-2025-66026 is a security vulnerability in Redaxo/source involving REDAXO CMS is vulnerable to Reflected XSS in Mediapool Info Banner via args[types] under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting').
Which Redaxo/source versions are affected?
Affected versions include releases prior to 5.20.1 across affected packages: redaxo/source.
What version fixes CVE-2025-66026?
Upgrading to 5.20.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is redaxo/source affected?
Yes, redaxo/source is affected in releases prior to 5.20.1. Upgrade your dependency to 5.20.1 or later.
What is the CVSS score of CVE-2025-66026?
CVE-2025-66026 has a CVSS v3.1 base score of 6.1 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
What CWE is associated with CVE-2025-66026?
CVE-2025-66026 is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.).
How can I check Packagist dependencies for CVE-2025-66026?
Run the dependency tree command: 'inspect dependencies for redaxo/source'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-x6vr-q3vf-vqgq",
  "modified" : "2025-11-27T09:01:42Z",
  "published" : "2025-11-25T23:53:04Z",
  "aliases" : [ "CVE-2025-66026" ],
  "summary" : "REDAXO CMS is vulnerable to Reflected XSS in Mediapool Info Banner via args[types]",
  "details" : "### Summary\nA reflected Cross-Site Scripting (XSS) vulnerability exists in the Mediapool view where the request parameter `args[types]` is rendered into an info banner without HTML-escaping. This allows arbitrary JavaScript execution in the backend context when an authenticated user visits a crafted link while logged in.\n\n### Details\n\nControl Flow:\n\n1. `redaxo/src/addons/mediapool/pages/index.php` reads args via `rex_request('args', 'array')` and passes them through as `$argUrl` to `media.list.php`.\n2. `redaxo/src/addons/mediapool/pages/media.list.php` injects `$argUrl['args']['types']` into an HTML string without escaping:\n\n```\nif (!empty($argUrl['args']['types'])) {\n    echo rex_view::info(rex_i18n::msg('pool_file_filter') . ' <code>' . $argUrl['args']['types'] . '</code>');\n}\n```\n\n### PoC\n\n1. Log into the REDAXO backend.\n2. While authenticated, open a crafted URL like: `<host>/index.php?page=mediapool/media&args[types]=\"><img+src%3Dx+onerror%3Dalert%28document.domain%29>`\n4. The info banner displays the unescaped value and activates the injected onerror handler, which opens an alert pop-up.\n\n### Impact\nArbitrary JavaScript execution in the backend, enabling theft of session cookies, CSRF tokens, or other sensitive data, and allowing an attacker to perform any administrative actions on behalf of the affected user.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "redaxo/source"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "5.20.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/redaxo/redaxo/security/advisories/GHSA-x6vr-q3vf-vqgq"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-66026"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/redaxo/redaxo/commit/58929062312cf03e344ab04067a365e6b6ee66aa"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/redaxo/redaxo"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-11-25T23:53:04Z",
    "nvd_published_at" : "2025-11-26T03:15:58Z"
  }
}