What’s Vulnerable › Vulnerabilities

CVE-2026-5820: Zypento Blocks <= 1.0.6 - Authenticated (Author+) Stored Cross-Site Scripting via Table of Contents Block

• Severity: medium (CVSS 6.4 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-04-22 · updated 2026-06-17
• Weakness: CWE-79

Description

The Zypento Blocks plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the Table of Contents block in all versions up to, and including, 1.0.6. This is due to the front-end TOC rendering script reading heading text via `innerText` and inserting it into the page using `innerHTML` without proper sanitization. This makes it possible for authenticated attackers, with Author-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Affected products

• sproutient Zypento Blocks: through 1.06

References

• https://plugins.trac.wordpress.org/browser/zypento-blocks/tags/1.0.6/assets/js/src/blocks/table-of-contents/view.js#L57
• https://plugins.trac.wordpress.org/browser/zypento-blocks/tags/1.0.6/assets/js/src/blocks/table-of-contents/view.js#L71
• https://www.wordfence.com/threat-intel/vulnerabilities/id/024a6a0f-f819-40e7-9618-71219c27aa64?source=cve

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