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vulnerability

WordPress Plugin: fathom-analytics: CVE-2021-41836: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Severity
3
CVSS
(AV:N/AC:M/Au:S/C:N/I:P/A:N)
Published
Dec 8, 2021
Added
May 15, 2025
Modified
May 5, 2026

Description

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.

Solution

fathom-analytics-plugin-cve-2021-41836
Title
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