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.
CVE-2021-41836 is a medium severity with CVSS 4.8 Stored Cross-Site Scripting issue affecting the Plugin Fathom Analytics for WP. It affects Versions up to 3.0.4 and is fixed in 3.0.5.
Use the related hub and response guides to connect this CVE-2021-41836 report with patch validation, scanner checks, and site hardening work.
Open the grouped hub for related CVEs, affected ranges, severity mix, and patch coverage.
Check access, XML-RPC exposure, backup readiness, and monitoring after patching.
Use containment, evidence capture, remediation, and validation steps when exploit risk is high.
CVE-2021-41836 is tracked for the Plugin Fathom Analytics for WP as medium severity with CVSS 4.8. The affected range is Versions up to 3.0.4. Update Fathom Analytics for WP to 3.0.5 or newer where that version is compatible with the site.
Search engines and operators need more than a title. This page exposes the identifier, affected range, patch evidence, and source coverage that make the vulnerability actionable.
This report has a CVE identifier, which makes it suitable for focused search and vulnerability triage workflows.
Affected version data gives operators a concrete comparison point against installed WordPress software.
A fixed version is present, so the page can answer update and remediation intent directly.
External references are available for source validation, advisory review, and incident notes.
Use these checks when converting this record into a patch ticket, incident note, or risk acceptance decision.
Inventory the installed Plugin package and compare its version with Versions up to 3.0.4.
Confirm Fathom Analytics for WP is updated to 3.0.5 or newer.
Review references and CVSS vector details for exploitability, authentication requirements, and exposure path.
After patching, re-run vulnerability monitoring and keep the related plugin or theme hub under review for follow-up CVEs.
| Software Type | Plugin |
|---|---|
| Software Slug |
fathom-analytics
View on wordpress.org
|
| CVE | CVE-2021-41836 |
| Patched Versions |
3.0.5
|
| Affected Versions |
Versions up to 3.0.4
|
These internal links group the same WordPress plugin by CVE, issue type, severity, and patch status so operators and search engines can connect the full vulnerability cluster.
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