CVE-2026-2352: optimizingmatters autoptimize Cross-site Scripting

Vulnerability summary

CVE-2026-2352 is a medium (CVSS 6.4) Cross-site Scripting vulnerability in optimizingmatters autoptimize. EPSS estimates a 0.26% chance of exploitation in the next 30 days, higher than 16.6% of scored vulnerabilities. Fixed in 3.1.15.

Timeline

1. 20-03-2026
   PublishedVulnerability first disclosed.
2. 08-04-2026
   Last modifiedVulnerability information updated.

Description

The Autoptimize plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'ao_post_preload' meta value in all versions up to, and including, 3.1.14. This is due to insufficient input sanitization in the `ao_metabox_save()` function and missing output escaping when the value is rendered into a `<link>` tag in `autoptimizeImages.php`. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page, granted the "Image optimization" or "Lazy-load images" setting is enabled in the plugin configuration.

• CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.