CVE-2021-24436: W3 Total Cache < 2.1.4 - Reflected XSS in Extensions Page (Attribute Context)

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.9% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2021-07-19 · updated 2026-06-17
Weakness: CWE-79

Description

The W3 Total Cache WordPress plugin before 2.1.4 was vulnerable to a reflected Cross-Site Scripting (XSS) security vulnerability within the "extension" parameter in the Extensions dashboard, which is output in an attribute without being escaped first. This could allow an attacker, who can convince an authenticated admin into clicking a link, to run malicious JavaScript within the user's web browser, which could lead to full site compromise.

Affected products

boldgrid W3 Total Cache: before 2.1.4 — fixed in 2.1.4

How to fix

Upgrade to a fixed version: boldgrid W3 Total Cache 2.1.4. Check the vendor advisory for mitigations.

References

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