CVE-2026-3004 Overview
CVE-2026-3004 is a Stored Cross-Site Scripting (XSS) vulnerability in the Snow Monkey Blocks plugin for WordPress, affecting all versions up to and including 24.1.11. The flaw resides in the handling of the data-slick attribute, where insufficient input sanitization and output escaping allow authenticated users with Contributor-level access or higher to inject arbitrary web scripts. Injected payloads execute in the browser of any visitor accessing the affected page. The vulnerability is classified under CWE-79: Improper Neutralization of Input During Web Page Generation.
Critical Impact
Authenticated contributors can persistently inject JavaScript that executes against site visitors and administrators, enabling session theft, content defacement, and privilege escalation through admin-targeted payloads.
Affected Products
- Snow Monkey Blocks plugin for WordPress, all versions through 24.1.11
- WordPress sites with Contributor-level or higher user registration enabled
- Sites publishing content authored by users with the Snow Monkey Blocks editor capability
Discovery Timeline
- 2026-05-13 - CVE-2026-3004 published to NVD
- 2026-05-13 - Last updated in NVD database
Technical Details for CVE-2026-3004
Vulnerability Analysis
The vulnerability stems from improper handling of the data-slick attribute used by the Snow Monkey Blocks plugin to configure slider behavior. The plugin accepts attribute values supplied through block editor input and renders them into page markup without adequate sanitization or output escaping. An authenticated attacker with Contributor privileges can craft a block payload containing JavaScript inside the data-slick attribute. When a visitor loads the rendered page, the browser parses the injected script in the context of the site origin.
Because the injected content persists in the WordPress database, every subsequent page view triggers script execution. The Scope:Changed component of the CVSS vector reflects the cross-origin impact on user browsers. Successful exploitation can lead to cookie theft, forced administrative actions via CSRF, and chained privilege escalation when administrators preview or review contributor-submitted content.
Root Cause
The root cause is missing input sanitization at content ingestion and missing output escaping at render time. The plugin trusts the data-slick attribute content provided through editor blocks and serializes it directly into HTML. Relevant rendering logic appears in snow-monkey-blocks.php, referenced in the WordPress Plugin Code View at line 228 and line 45.
Attack Vector
Exploitation requires network access to the WordPress site and an authenticated account with Contributor capabilities or higher. The attacker creates or edits a post containing a Snow Monkey block, injects a JavaScript payload into the data-slick attribute via the block editor or REST API, and submits the content. When an editor, administrator, or site visitor renders the page, the script executes in their browser session.
No code example is included because no verified proof-of-concept has been published. Refer to the Wordfence Vulnerability Report for additional technical context.
Detection Methods for CVE-2026-3004
Indicators of Compromise
- Post or page content containing data-slick attributes with values that include <script>, javascript:, or HTML event handlers such as onerror= and onload=
- Unexpected outbound requests from visitor browsers to attacker-controlled domains shortly after viewing pages built with Snow Monkey Blocks
- Contributor accounts publishing or submitting posts containing custom HTML attributes inside slider or carousel blocks
Detection Strategies
- Query the wp_posts table for post_content entries containing data-slick= followed by suspicious characters such as angle brackets, encoded entities, or javascript: schemes
- Review WordPress audit logs for Contributor-level accounts performing repeated post edits to blocks rendered by Snow Monkey Blocks
- Inspect server response bodies for data-slick attributes containing executable content using a web application firewall or proxy-based content inspection rule
Monitoring Recommendations
- Enable verbose logging for WordPress REST API endpoints /wp/v2/posts and /wp/v2/pages to capture contributor submissions for review
- Monitor Content Security Policy (CSP) violation reports for inline script execution originating from pages containing Snow Monkey blocks
- Track newly created or recently elevated Contributor accounts and correlate with post creation activity targeting pages with slider blocks
How to Mitigate CVE-2026-3004
Immediate Actions Required
- Update the Snow Monkey Blocks plugin to the version released in WordPress Changeset 3519092, which contains the official fix
- Audit all existing posts and pages rendered by Snow Monkey Blocks for unexpected data-slick attribute content and remove any malicious payloads
- Review and restrict Contributor-level accounts, removing accounts that are inactive or unverified
Patch Information
The vendor addressed the vulnerability in WordPress Changeset 3519092, which introduces proper sanitization and output escaping for the data-slick attribute. Site administrators should update through the WordPress plugin manager or by deploying the patched release from the WordPress plugin repository.
Workarounds
- Disable the Snow Monkey Blocks plugin until the patched version is deployed
- Restrict the Contributor role from publishing or submitting content containing custom block markup by limiting unfiltered_html capabilities and reviewing editor permissions
- Deploy a web application firewall rule that blocks HTTP requests where data-slick attribute values contain <, >, or javascript: substrings
# Configuration example: WP-CLI command to update the plugin
wp plugin update snow-monkey-blocks --version=latest
# Verify installed version after update
wp plugin get snow-monkey-blocks --field=version
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
