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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
Low
Partial data leak
Integrity
Low
Partial data modification
Availability
None
No disruption
CVSS Vector v3.1
Weakness Type (CWE)
References 6
https://plugins.trac.wordpress.org/browser/w3-total-cache/tags/2.10.6/BrowserCa…
security@wordfence.com
https://plugins.trac.wordpress.org/browser/w3-total-cache/tags/2.10.6/BrowserCa…
security@wordfence.com
https://plugins.trac.wordpress.org/browser/w3-total-cache/tags/2.10.6/BrowserCa…
security@wordfence.com
https://plugins.trac.wordpress.org/changeset/3723494/w3-total-cache/trunk/Brows…
security@wordfence.com
https://plugins.trac.wordpress.org/changeset?reponame=&new=3723494%40w3-total-c…
security@wordfence.com
https://www.wordfence.com/threat-intel/vulnerabilities/id/34bd7c32-f4c5-4015-90…
security@wordfence.com