XSS in Livecomposer Live Composer – Free WordPress Website Builder

CVE-2026-16786

The Live Composer – Free WordPress Website Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via dslc_module_testimonials_output Shortcode in all versions up to, and including, 2.1.19 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 injected payload survives save-time wp_kses_post filtering because KSES treats shortcode delimiters as opaque, and the unescaped fields — including main_heading_title, view_all_link, main_heading_link_title, and main_filter_title_all — are only rendered when do_shortcode() executes at page-view time.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

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.

EPSS exploit prediction

EPSS: 0.002 (9.3th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 9th percentile — 9.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-16786: held from 0.003 to 0.002.

EPSS over last 30 days · oldest: 0.003 · newest: 0.002 · change: -0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-16786?
CVE-2026-16786 is a medium-severity vulnerability in Livecomposer Live Composer – Free WordPress Website Builder, classified under Cross-site Scripting. CVSS score: 6.4/10. Published 2026-09-01.
How severe is CVE-2026-16786?
Medium severity. CVSS v3 base score is 6.4 out of 10.