CVE-2026-110290

The WebberZone Top 10 — Popular Posts plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'other_attributes (parsed to inject instance_id) + undeclared is_widget' parameter in all versions up to, and including, 4.5.2 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 exploit requires setting the undeclared is_widget flag to '1' via block JSON, which activates the vulnerable code path that concatenates the attacker-controlled instance_id value into an unescaped HTML class attribute.

• https://plugins.trac.wordpress.org/browser/top-10/tags/4.5.2/includes/frontend/blocks/class-blocks.php#L128
• https://plugins.trac.wordpress.org/browser/top-10/tags/4.5.2/includes/frontend/blocks/class-blocks.php#L142
• https://plugins.trac.wordpress.org/browser/top-10/tags/4.5.2/includes/frontend/class-display.php#L153
• https://plugins.trac.wordpress.org/browser/top-10/tags/4.5.2/includes/frontend/class-display.php#L170
• https://plugins.trac.wordpress.org/browser/top-10/tags/4.5.2/includes/util/class-helpers.php#L693
• https://plugins.trac.wordpress.org/browser/top-10/tags/4.5.3/includes/frontend/class-display.php
• https://plugins.trac.wordpress.org/changeset/3747022
• https://www.wordfence.com/threat-intel/vulnerabilities/id/4db4a201-a7fa-4764-87cb-c54b64adf560?source=cve

• MEDIUMCVE-2016-20098PoC
• MEDIUMCVE-2023-54408PoC
• UNSCOREDCVE-2023-5648
• MEDIUMCVE-2024-31027
• MEDIUMCVE-2024-34321
• MEDIUMCVE-2024-58391PoC
• MEDIUMCVE-2025-12828
• MEDIUMCVE-2025-13533PoC

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