Vulnerability Description
The WPSpeed plugin for WordPress is vulnerable to Stored Cross-Site Scripting in versions up to, and including, 2.6.10 This is due to a combination of two issues in the LightImages HTML optimizer: (1) Dispatcher::runOptimize() decides whether the current request is the site's home page by comparing only the URL path from REQUEST_URI against the path of the home URL, so on a plain-permalinks install the author archive URL /?author=<ID> is treated as the home page and the LightImages optimizer runs on it; and (2) LightImages::optimize() calls html_entity_decode() across the entire serialized DOMDocument output under the default-enabled img_processing_entity_decode setting, converting any entity-encoded markup present as plain text in the page (including WordPress's rendered author title) into live HTML. This makes it possible for authenticated attackers, with Subscriber-level access and above, to store entity-encoded markup in their own nickname/display_name through the normal profile endpoint and have that markup rehydrated into executing script when any logged-out visitor loads their author archive.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://plugins.trac.wordpress.org/browser/wpspeed/tags/2.6.10/src/Core/LightIma
- https://plugins.trac.wordpress.org/browser/wpspeed/tags/2.6.10/src/Core/Optimize
- https://plugins.trac.wordpress.org/browser/wpspeed/tags/2.6.10/src/Dispatcher.ph
- https://plugins.trac.wordpress.org/changeset/3771695/wpspeed/trunk/src/Core/Ligh
- https://www.wordfence.com/threat-intel/vulnerabilities/id/47aa1a74-4189-4521-ba6
FAQ
What is CVE-2026-118784?
CVE-2026-118784 is a vulnerability with a CVSS score of 6.4 (MEDIUM). The WPSpeed plugin for WordPress is vulnerable to Stored Cross-Site Scripting in versions up to, and including, 2.6.10 This is due to a combination of two issues in the LightImages HTML optimizer: (1)...
How severe is CVE-2026-118784?
CVE-2026-118784 has been rated MEDIUM with a CVSS base score of 6.4/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-118784?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.