XSS in 3uu Shariff Wrapper

CVE-2026-4334

The Shariff Wrapper plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'headline' parameter in the [shariff] shortcode in all versions up to, and including, 4.6.20 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 vulnerability occurs because the plugin uses a custom wp_kses implementation with permissive allowed HTML tags, and then performs a str_replace operation that injects HTML after sanitization, allowing event handlers to be introduced through the %total placeholder in the style attribute.

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: 0.003 (26.1th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 26th percentile — 26.1% 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-2026-4334: held from 0.002 to 0.003.

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

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-4334?
CVE-2026-4334 is a medium-severity vulnerability in 3uu Shariff Wrapper, classified under Cross-site Scripting. CVSS score: 6.4/10. Published 2026-05-28.
How severe is CVE-2026-4334?
Medium severity. CVSS v3 base score is 6.4 out of 10.