Vulnerability · Published Oct 2, 2026 · Assigned by Wordfence
CVE-2026-87920W3 Total Cache <= 2.10.6 - Unauthenticated Stored Cross-Site Scripting via Comment Content
High 7.2
In plain English
A high-severity cross-site scripting in W3 Total Cache from boldgrid. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 15% of all known vulnerabilities).
Official description
The W3 Total Cache plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Comment Content via Output-Buffer Regex Rewrite in all versions up to, and including, 2.10.6 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This vulnerability is only exploitable when the 'Remove query strings from static resources' option is enabled in W3 Total Cache, as mutate_url() must strip the '?' delimiter and everything following it — including the closing quote of the outer attribute — to break the attribute boundary.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| boldgrid | W3 Total Cache | 0 – through 2.10.6 |
Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
References
- https://www.wordfence.com/threat-intel/vulnerabilities/id/34bd7c32-f4c5-4015-909a-e4730f35494b?source=cve
- https://plugins.trac.wordpress.org/browser/w3-total-cache/tags/2.10.6/BrowserCache_Plugin.php#L259
- https://plugins.trac.wordpress.org/browser/w3-total-cache/tags/2.10.6/BrowserCache_Plugin.php#L208
- https://plugins.trac.wordpress.org/browser/w3-total-cache/tags/2.10.6/BrowserCache_Plugin.php#L336
- https://plugins.trac.wordpress.org/changeset?reponame=&new=3723494%40w3-total-cache%2Ftags%2F2.10.7&old=3681561%40w3-total-cache%2Ftags%2F2.10.6
- https://plugins.trac.wordpress.org/changeset/3723494/w3-total-cache/trunk/BrowserCache_Plugin.php