CVE-2026-15446

medium

Description

The EWWW Image Optimizer plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'data-script' Lazy Load Attribute in Post Content in all versions up to, and including, 8.7.3 due to insufficient input sanitization and output escaping. 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. The exploit is achieved by embedding a crafted img element with class='lazyload' and a data-script attribute pointing to an attacker-controlled URL in post content, which the plugin's bundled lazysizes ls.unveilhooks addon then uses to dynamically create and insert a script element into the DOM at page view time.

References

https://www.wordfence.com/threat-intel/vulnerabilities/id/e8af1fdb-7fec-4bbe-937b-ee2e76cf5c5b?source=cve

https://plugins.trac.wordpress.org/browser/ewww-image-optimizer/tags/8.7.3/includes/ls.unveilhooks.js#L178

https://plugins.trac.wordpress.org/browser/ewww-image-optimizer/tags/8.7.3/includes/ls.unveilhooks.js#L116

https://plugins.trac.wordpress.org/browser/ewww-image-optimizer/tags/8.7.3/classes/class-lazy-load.php#L496

https://plugins.trac.wordpress.org/browser/ewww-image-optimizer/tags/8.7.3/classes/class-lazy-load.php#L1679

https://plugins.trac.wordpress.org/browser/ewww-image-optimizer/tags/8.6.0/includes/ls.unveilhooks.js#L178

https://plugins.trac.wordpress.org/browser/ewww-image-optimizer/tags/8.6.0/includes/ls.unveilhooks.js#L116

https://plugins.trac.wordpress.org/browser/ewww-image-optimizer/tags/8.6.0/classes/class-lazy-load.php#L496

https://plugins.trac.wordpress.org/browser/ewww-image-optimizer/tags/8.6.0/classes/class-lazy-load.php#L1679

https://github.com/nosilver4u/ewww-image-optimizer/commit/4488aafaee9212db370a5ed2dcb9bad7912b897d

Details

Source: Mitre, NVD

Published: 2026-08-19

Updated: 2026-08-19

Risk Information

CVSS v2

Base Score: 5.5

Vector: CVSS2#AV:N/AC:L/Au:S/C:P/I:P/A:N

Severity: Medium

CVSS v3

Base Score: 6.4

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

Severity: Medium