CVE-2026-4665

What is known

The WP Carousel Free plugin for WordPress is vulnerable to Stored Cross-Site Scripting via crafted fancybox `data-caption` attributes in all versions up to, and including, 2.7.10. This is due to the `fancybox-config.js` script reading the carousel container's `id` attribute directly from the DOM to construct a jQuery selector without sanitization. When a Contributor crafts an HTML block with a malformed carousel container ID (containing characters invalid for jQuery selectors), the custom fancybox configuration throws a JavaScript error and fails to initialize. This causes the bundled fancybox library (v3.5.7) to fall back to its default caption handling, which renders the `data-caption` attribute content as raw HTML. Since WordPress allows `data-*` attributes through `wp_kses_post()`, 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 clicks an image in the crafted carousel lightbox.

Business impact

Successful exploitation of CVE-2026-4665, a medium vulnerability (CVSS 6.4) affecting the affected product, may affect the confidentiality, integrity or availability of the vulnerable environment. The exact impact depends on the installed version, exposed interfaces and deployment configuration.

Recommended administrator action

Confirm whether the affected product is present and compare installed versions with the vendor advisory and NVD record. Apply the vendor patch or documented mitigation; until remediation is complete, reduce exposure of affected interfaces, review relevant logs and monitor for indicators of exploitation. DataHouse can support version verification, managed patching, network exposure reduction, log review and backup validation for dedicated, cloud and colocated environments.

Sources

• NVD
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