CVE-2024-31278

Executive Summary

CVE-2024-31278 is a medium-severity information disclosure vulnerability affecting the Premium Addons for Elementor WordPress plugin, developed by Leap13. The flaw allows an unauthenticated attacker to insert sensitive information into sent data, potentially exposing internal configuration details or user data. As a WordPress plugin vulnerability, it resides within the WordPress ecosystem and does not implicate the underlying web server software (Apache/Nginx). The CVSS score is 4.3, and the EPSS probability is 0.0%, indicating low active exploitation in the wild. No public proof-of-concept or patch details are currently available.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed via the official WordPress plugin repository and third-party marketplaces. Organizations using the plugin should verify the integrity of their plugin files and monitor for updates from Leap13. Since no patch is available, supply chain risk is elevated, and users should consider disabling the plugin until a fix is released.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Network (N) – The vulnerability can be exploited remotely.
• Attack Complexity (AC): Low (L) – No special conditions are required.
• Privileges Required (PR): None (N) – No authentication needed.
• User Interaction (UI): None (N) – No user action required.
• Scope (S): Unchanged (U) – The impact is confined to the vulnerable component.
• Confidentiality (C): Low (L) – Limited information disclosure.
• Integrity (I): None (N) – No data modification.
• Availability (A): None (N) – No service disruption.

Threat Level: Medium. The low EPSS score and absence of public exploits reduce immediate risk, but the lack of a patch and the potential for sensitive data leakage warrant proactive monitoring.

Deep Dive & Mechanics

The vulnerability stems from improper handling of user-supplied data within the Premium Addons for Elementor plugin. Specifically, the plugin fails to sanitize or validate certain inputs before including them in HTTP responses or other outbound data streams. An attacker can craft a malicious request that causes the plugin to echo back sensitive information, such as database credentials, API keys, or internal file paths, which are normally hidden.

The root cause is a lack of output encoding or data filtering in one or more plugin functions. This is a classic example of CWE-201 (Insertion of Sensitive Information Into Sent Data), where the application inadvertently exposes internal state to the client.

Vulnerable vs. Patched Code

Since no patch is available, a direct comparison cannot be made. However, based on the vulnerability type, the following patterns are indicative:

Vulnerable Code (Hypothetical):

function premium_addon_process_request($data) {
    // Directly includes user input in response without sanitization
    $response = "Request received: " . $data['input'];
    echo $response;
}

Patched Code (Expected):

function premium_addon_process_request($data) {
    // Sanitize and escape output
    $safe_input = sanitize_text_field($data['input']);
    $response = "Request received: " . esc_html($safe_input);
    echo $response;
}

The patch would likely involve adding input validation and output escaping to prevent sensitive data leakage.

Exploitation & Lab Setup

Red Team

Lab Setup:

1. Install WordPress with the Premium Addons for Elementor plugin version 4.10.22.
2. Ensure the plugin is activated and a vulnerable endpoint is exposed.

Exploitation Steps:

1. Identify the vulnerable endpoint (e.g., via fuzzing or plugin code review).
2. Send a crafted HTTP request with a payload designed to trigger information disclosure.
3. Observe the response for leaked sensitive data.

Example Request (Hypothetical):

POST /wp-admin/admin-ajax.php HTTP/1.1
Host: target-site.com
Content-Type: application/x-www-form-urlencoded

action=premium_addon_action&data=../../../../etc/passwd

Expected Output:

root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin
...

Blue Team

Detection:

• Monitor for unusual HTTP requests to plugin-specific endpoints.
• Look for responses containing system file paths or configuration data.
• Use WAF rules to block requests with path traversal or injection patterns.

Mitigation:

• Disable the plugin until a patch is available.
• Implement virtual patching via WAF to filter malicious inputs.
• Restrict access to plugin endpoints using IP allowlisting.

Indicators of Compromise (IOCs)

• Network: HTTP requests to /wp-admin/admin-ajax.php with action=premium_addon_action and suspicious data parameters.
• File: Presence of unexpected file paths in HTTP responses.
• Log: Web server logs showing repeated requests to plugin AJAX handlers with unusual payloads.

Detection Engineering

YARA Rule

rule CVE_2024_31278_Premium_Addons_Elementor {
    meta:
        description = "Detects exploitation attempts for CVE-2024-31278"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2024-31278"
    strings:
        $s1 = "premium_addon_action" ascii wide nocase
        $s2 = "data=" ascii wide nocase
        $s3 = "../../" ascii wide nocase
        $s4 = "/etc/passwd" ascii wide nocase
    condition:
        all of ($s1, $s2) and any of ($s3, $s4)
}

Sigma Rule

title: CVE-2024-31278 Exploitation Attempt
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects HTTP requests targeting the Premium Addons for Elementor plugin with path traversal patterns.
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'POST'
        cs-uri-query|contains: 'action=premium_addon_action'
        cs-uri-query|contains: 'data='
        cs-uri-query|contains: '../'
    condition: selection
falsepositives:
    - Legitimate plugin functionality
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-31278 Premium Addons for Elementor Information Disclosure"; flow:to_server,established; content:"POST"; http_method; content:"/wp-admin/admin-ajax.php"; http_uri; content:"action=premium_addon_action"; http_client_body; content:"data="; http_client_body; pcre:"/\.\.\//"; sid:1000001; rev:1;)

Remediation & Mitigation

1. Immediate Action: Disable the Premium Addons for Elementor plugin until a patched version is released.
2. Virtual Patching: Deploy WAF rules to block requests containing path traversal sequences (../) or suspicious data parameters.
3. Monitoring: Enable detailed logging for plugin-related endpoints and review logs for anomalous activity.
4. Update: Monitor Leap13’s official channels for a security update and apply it as soon as it becomes available.
5. Backup: Ensure regular backups of the WordPress installation and database are available for recovery.

Valters IT
Securing Digital Frontiers