CVE-2026-2430: optimizingmatters autoptimize Cross-site Scripting

Vulnerability summary

CVE-2026-2430 is a medium (CVSS 6.4) Cross-site Scripting vulnerability in optimizingmatters autoptimize. EPSS estimates a 0.21% chance of exploitation in the next 30 days, higher than 9.9% 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 lazy-loading image processing in all versions up to, and including, 3.1.14. This is due to the use of an overly permissive regular expression in the `add_lazyload` function that replaces all occurrences of `\ssrc=` in image tags without limiting to the actual attribute. 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 by crafting an image tag where the `src` URL contains a space followed by `src=`, causing the regex to break the HTML structure and promote text inside attribute values into executable HTML attributes.

• 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.