Name: CVE-2021-41836: Improper Neutralization of Input During Web Page Generation
Creator: Rapid7
Published: 2021-12-14T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2021-41836, CWE-79, CVSS 4.8, EPSS 0.00304

The Fathom Analytics WordPress plugin is vulnerable to Stored Cross-Site Scripting due to insufficient input validation and escaping via the $site_id parameter found in the ~/fathom-analytics.php file which allowed attackers with administrative user access to inject arbitrary web scripts, in versions up to and including 3.0.4. This affects multi-site installations where unfiltered_html is disabled for administrators, and sites where unfiltered_html is disabled.

CVSS Details

CVSS 3.1 Base Score: 4.8
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Fathom Analytics Plugin	—	Update fathom-analytics plugin to version 3.0.5, or a newer patched version	May 15, 2025	Dec 8, 2021

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CVSS Details

Covered by Rapid7

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