CVE-2025-8399

Mmm Unity Loader <= 1.0 - Authenticated (Contributor+) Stored Cross-Site Scripting via attributes Parameter

Published Aug 2, 2025 CVSS 3.1 · 6.4 Medium EPSS < 1% KEV · Not listed
Description
The Mmm Unity Loader plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘attributes’ parameter in all versions up to, and including, 1.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Analysis

AI-generated

Technical impact

The vulnerability in the Mmm Unity Loader plugin permits the storage of malicious JavaScript through the attributes parameter. When a page that contains the injected content is viewed, the browser executes the script, which could be used to steal session cookies, deface content, or perform other client‑side attacks. The impact is limited to the client’s browser execution context, but it can affect all visitors to the offending page.

Affected Systems

All versions of the Mmm Unity Loader WordPress plugin up to and including 1.0, distributed by mmanifesto and listed on the WordPress plugin repository. The issue applies to any WordPress installation that has these plugins installed and permits Contributor‑level or higher users to edit content via the plugin’s attributes field.

Risk and Exploitability

The CVSS score of 6.4 indicates moderate overall risk. An EPSS score of less than 1% suggests exploitation is unlikely at present, and the vulnerability is not listed in the CISA KEV catalog. Exploitation requires an attacker to be logged in to WordPress with Contributor or higher privileges and to use the plugin’s attributes input to store malicious code. Once the code is stored, it will run automatically for any user who accesses the affected page, making it a stealthy but client‑side attack vector.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Upgrade the Mmm Unity Loader plugin to the latest version that removes the vulnerable attributes field.
  • If an upgrade is not yet available, delete or deactivate the plugin to eliminate the attack surface.
  • Restrict or remove Contributor‑level access on the WordPress site and audit existing content for injected scripts to prevent malicious code from remaining on live pages

Generated by OpenCVE AI on April 22, 2026 at 14:33 UTC.

Tracking

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Advisories

Source ID Title
EUVD EUVD EUVD-2025-23430 The Mmm Unity Loader plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘attributes’ parameter in all versions up to, and including, 1.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
History
Type Values Removed Values Added
First Time appeared Mediamanifesto
Mediamanifesto mmm Unity Loader
Wordpress
Wordpress wordpress
Vendors & Products Mediamanifesto
Mediamanifesto mmm Unity Loader
Wordpress
Wordpress wordpress
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description The Mmm Unity Loader plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘attributes’ parameter in all versions up to, and including, 1.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
Title Mmm Unity Loader <= 1.0 - Authenticated (Contributor+) Stored Cross-Site Scripting via attributes Parameter
Weaknesses CWE-79
References
Metrics cvssV3_1

{'score': 6.4, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N'}

Weaknesses
  • CWE-79

    Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Sources

Status
PUBLISHED
Assigner
Wordfence
Published
Updated
Apr 8, 2026, 4:44 PM
Reserved
Jul 30, 2025, 10:51 PM
Status
Deferred
Published
Aug 2, 2025, 9:15 AM
Modified
Jun 17, 2026, 10:06 AM