---
id: "CVE-2026-110290"
kind: "vulnerability"
aliases: ["CVE-2026-110290"]
title: "WebberZone Top 10 WordPress plugin: stored XSS through block attributes"
severity: "medium"
cvss: 6.4
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["package", "self-hosted", "wordpress", "wordpress-plugin"]
not_affected_if: ["no-untrusted-contributors", "plugin-not-installed", "plugin-updated"]
published_at: "2026-10-16T07:17:11+00:00"
first_seen_at: "2026-10-23T21:57:12+00:00"
updated_at: "2026-10-25T03:59:50+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-110290", "first_seen_at": "2026-10-23T21:57:12+00:00"}]
---

# WebberZone Top 10 WordPress plugin: stored XSS through block attributes

The WebberZone Top 10 Popular Posts plugin for WordPress up to and including 4.5.2 does not sanitize the instance_id attribute it writes into an HTML class, so the attribute can carry script. An attacker with contributor-level access can store a script in a page that runs in the browser of any user who opens it.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed version of the WebberZone Top 10 plugin in the WordPress admin plugin list or with `wp plugin get top-10 --field=version`
- Review pages and posts for Top 10 blocks with unexpected script content in their block attributes

## Fix

- Update the WebberZone Top 10 plugin to a version later than `4.5.2` (the sources do not name the fixed release)

## Timeline

- 2026-10-23T21:57:12+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-110290

## From the sources

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.

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