XSS in Metaslider Slider, Gallery, And Carousel By – Image Video Slider
CVE-2026-18400
The Slider, Gallery, and Carousel by MetaSlider – Image Slider, Video Slider plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'delay' Post Meta Setting in all versions up to, and including, 3.111.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with custom-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The ml-slider custom post type is registered without custom capability restrictions and the ml-slider_settings meta key is unprotected, allowing Author-level users to set the malicious delay value via XML-RPC custom_fields when creating an ml-slider post.
Vulnerability class: XSS (Cross-Site Scripting)
EPSS: 0.002 (15.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N.
Affected products
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-18400?
- CVE-2026-18400 is a medium-severity vulnerability in Metaslider Slider, Gallery, And Carousel By – Image Video Slider, classified under Cross-site Scripting. CVSS score: 6.4/10. Published 2026-08-06.
- How severe is CVE-2026-18400?
- Medium severity. CVSS v3 base score is 6.4 out of 10.