CVE-2024-54264: Shortcodes Blocks Creator XSS Flaw

CVE-2024-54264 Overview

CVE-2024-54264 is a reflected cross-site scripting (XSS) vulnerability in the Shortcodes Blocks Creator Ultimate WordPress plugin developed by cmorillas1. The flaw affects all plugin versions from initial release through 2.2.0. The issue stems from improper neutralization of user-supplied input during web page generation [CWE-79]. Attackers can craft malicious URLs that execute arbitrary JavaScript in a victim's browser when the link is clicked. Successful exploitation requires user interaction and can lead to session theft, credential harvesting, or actions performed on behalf of the victim within the WordPress site context.

Critical Impact

Attackers can hijack authenticated administrator sessions, steal sensitive data, and perform privileged actions on affected WordPress installations through crafted phishing links.

Affected Products

• cmorillas1 Shortcodes Blocks Creator Ultimate (ultimate-shortcodes-creator) plugin for WordPress
• All versions up to and including 2.2.0
• WordPress sites with the vulnerable plugin installed and active

Discovery Timeline

• 2024-12-13 - CVE-2024-54264 published to the National Vulnerability Database
• 2026-04-23 - Last updated in NVD database

Technical Details for CVE-2024-54264

Vulnerability Analysis

The vulnerability is a reflected XSS flaw in the Shortcodes Blocks Creator Ultimate WordPress plugin. The plugin fails to properly sanitize and encode user-controlled input before reflecting it back in HTTP responses. An attacker who tricks an authenticated user into visiting a crafted URL can execute arbitrary JavaScript in the user's browser context. The scope is changed, meaning script execution can affect resources beyond the vulnerable component itself. Confidentiality, integrity, and availability impacts are each rated low, reflecting limited but tangible damage potential within the victim's browser session.

Root Cause

The root cause is improper neutralization of input during web page generation [CWE-79]. The plugin accepts request parameters and embeds them into HTML output without applying contextual output encoding or input validation. This allows HTML and JavaScript payloads to be rendered as executable markup in the response page.

Attack Vector

Exploitation occurs over the network and requires user interaction. The attacker constructs a URL containing a malicious JavaScript payload targeting a vulnerable endpoint exposed by the plugin. The attacker then delivers the link through phishing, social media, or a compromised site. When a victim clicks the link, the payload is reflected by the vulnerable parameter and executed in the browser. No authentication is required to craft the payload, but the impact scales with the privileges of the victim who triggers it. Detailed reproduction steps are available in the Patchstack WordPress Vulnerability Advisory.

Detection Methods for CVE-2024-54264

Indicators of Compromise

• Web server access logs containing requests to plugin endpoints with URL parameters including <script>, javascript:, onerror=, or HTML-encoded variants of these strings
• Unusual outbound requests from WordPress admin user sessions to attacker-controlled domains shortly after clicking external links
• Referrer headers from phishing domains or URL shorteners pointing at plugin pages

Detection Strategies

• Inspect HTTP request logs for query strings targeting ultimate-shortcodes-creator plugin paths containing script tags or event handler attributes
• Deploy a web application firewall (WAF) rule that blocks reflected XSS payloads on endpoints registered by the plugin
• Correlate browser-side Content Security Policy (CSP) violation reports with WordPress admin activity to surface attempted script injection

Monitoring Recommendations

• Enable verbose logging on the WordPress site and forward access logs to a centralized SIEM for retroactive search of XSS payload patterns
• Monitor administrator account activity for anomalous configuration changes, new user creation, or plugin modifications following suspicious link clicks
• Track outbound DNS queries from admin workstations for newly registered or low-reputation domains

How to Mitigate CVE-2024-54264

Immediate Actions Required

• Update Shortcodes Blocks Creator Ultimate to a version higher than 2.2.0 once the vendor publishes a patched release
• If no patched version is available, deactivate and remove the plugin from affected WordPress installations
• Force a password reset and session invalidation for all WordPress administrators who may have clicked untrusted links

Patch Information

At the time of CVE publication, the vulnerability affects versions up to and including 2.2.0. Administrators should consult the Patchstack advisory for the latest fixed version and remediation guidance.

Workarounds

• Deploy a WAF with rules that filter reflected XSS payloads on requests to plugin endpoints
• Implement a strict Content Security Policy (CSP) that disallows inline scripts and restricts script sources to trusted origins
• Restrict plugin admin pages to specific source IP ranges using server-level access controls until a patch is applied

# Example nginx configuration to add a strict Content Security Policy header
add_header Content-Security-Policy "default-src 'self'; script-src 'self'; object-src 'none'; base-uri 'self'; frame-ancestors 'self'" always;
add_header X-XSS-Protection "1; mode=block" always;
add_header X-Content-Type-Options "nosniff" always;