CVE-2026-16558: Unknown Ymc Filter

Medium severity, CVSS 5.4. EPSS: 0.2% chance of exploitation in the next 30 days.

The YMC Filter WordPress plugin before 3.12.8 does not sanitize and escape a layout builder setting before outputting it on a public endpoint, and does not verify object ownership when the setting is saved, allowing users with the Contributor role and above to store JavaScript that executes in the browser of any visitor viewing an affected filter.

Affected products

• Unknown Ymc Filter: from 3.6.0, before 3.12.8 (fixed in 3.12.8)

Published 2026-08-08. Last modified 2026-08-26.