VULNERABILITY INTELLIGENCE

CVE-2021-41836

CVSS score4.8 MEDIUM

EPSS probability0.58%

CISA KEVNot currently listed

Published2021-12-14

Last modified2026-06-17

CVSS vectorCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N

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.

Weakness classification

security@wordfence.com: CWE-79

Primary references

security@wordfence.com — Patch, Third Party Advisory
security@wordfence.com — Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108 — Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108 — Third Party Advisory