CVE-2025-66146

Executive Summary

CVE-2025-66146 is a Missing Authorization vulnerability in the Merkulove Logger for Elementor WordPress plugin, affecting versions up to and including 1.0.9. This flaw allows an unauthenticated attacker to exploit incorrectly configured access control security levels, potentially leading to unauthorized access to sensitive log data or manipulation of logging functionality. The vulnerability is classified as a WordPress ecosystem issue, not related to Apache or Nginx. The CVSS score is 5.4 (Medium), with a low EPSS score of 0.0%, indicating low active exploitation probability at this time. No public exploit code or patch is currently available.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed via the official WordPress plugin repository and potentially third-party marketplaces. Users should verify the integrity of their plugin installation and monitor for updates from the vendor. Since the patch status is unknown, supply chain risk is elevated for any site using this plugin.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
• Base Score: 5.4 (Medium)
• Attack Vector: Network (AV:N) – Exploitable remotely.
• Attack Complexity: Low (AC:L) – No special conditions required.
• Privileges Required: None (PR:N) – No authentication needed.
• User Interaction: None (UI:N) – No user action required.
• Scope: Unchanged (S:U) – Impact confined to the vulnerable component.
• Confidentiality Impact: Low (C:L) – Limited data exposure.
• Integrity Impact: Low (I:L) – Limited data modification.
• Availability Impact: None (A:N) – No denial of service.

Threat Level: Medium. While the CVSS score is moderate, the lack of required privileges and low attack complexity make this a viable target for automated scanning and exploitation, especially in WordPress environments with the plugin active.

Deep Dive & Mechanics

The vulnerability resides in the Logger for Elementor plugin's access control implementation. The plugin logs various events and actions within Elementor page builder. Due to missing authorization checks on certain AJAX actions or REST API endpoints, an unauthenticated attacker can:

1. Access Log Data: Retrieve sensitive information such as user activity, error logs, or debug data that may contain internal paths, usernames, or other metadata.
2. Modify Logging Settings: Potentially disable logging, clear logs, or alter log retention policies, affecting forensic capabilities.
3. Bypass Security Controls: Exploit the misconfigured access control to perform actions intended only for administrators.

The root cause is the failure to call current_user_can() or similar WordPress capability checks before executing privileged functions. The plugin likely registers AJAX handlers without verifying user roles.

Vulnerable vs. Patched Code

Since no patch is available, the vulnerable code pattern is inferred. A typical vulnerable snippet might look like:

// Vulnerable: No capability check
add_action('wp_ajax_nopriv_logger_get_logs', 'logger_get_logs');
function logger_get_logs() {
    // Process and return log data
    $logs = get_option('logger_elementor_logs');
    wp_send_json($logs);
}

A patched version would include:

// Patched: Capability check added
add_action('wp_ajax_logger_get_logs', 'logger_get_logs');
add_action('wp_ajax_nopriv_logger_get_logs', 'logger_get_logs_denied');
function logger_get_logs() {
    if (!current_user_can('manage_options')) {
        wp_die('Unauthorized', 403);
    }
    $logs = get_option('logger_elementor_logs');
    wp_send_json($logs);
}
function logger_get_logs_denied() {
    wp_die('Unauthorized', 403);
}

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• Target WordPress site with Logger for Elementor <= 1.0.9 installed and active.
• No authentication required.

Exploitation Steps:

1. Enumerate Endpoints: Identify AJAX actions used by the plugin (e.g., logger_get_logs, logger_clear_logs).
2. Craft Request: Send a POST request to the vulnerable endpoint without any authentication cookies.

curl -X POST https://target.com/wp-admin/admin-ajax.php \
  -d "action=logger_get_logs"

3. Extract Data: If successful, the response will contain log data in JSON format.

Note: No public exploit code is available; this is a conceptual demonstration.

Blue Team (Detection & Hardening)

Detection:

• Monitor for unusual AJAX requests to admin-ajax.php with actions related to "logger" from unauthenticated sources.
• Look for spikes in 403 errors followed by successful responses on the same endpoint.

Hardening:

• Disable the plugin until a patch is released.
• Implement a Web Application Firewall (WAF) rule to block unauthenticated access to known plugin AJAX actions.
• Use a security plugin like Wordfence to add virtual patching.

Indicators of Compromise (IOCs)

• Network IOCs:
  • POST requests to /wp-admin/admin-ajax.php with action=logger_get_logs or similar.
  • Responses containing JSON arrays with log entries.
• File IOCs:
  • Plugin directory: /wp-content/plugins/logger-elementor/
  • Version file: logger-elementor/readme.txt showing version <= 1.0.9.
• Log IOCs:
  • WordPress debug log entries showing unauthorized access attempts to plugin functions.

Detection Engineering

YARA Rule

rule Detect_Logger_Elementor_Vuln {
    meta:
        description = "Detects vulnerable Logger for Elementor plugin files"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-66146"
    strings:
        $vuln_func = "wp_ajax_nopriv_logger" nocase
        $vuln_file = "logger-elementor.php" nocase
    condition:
        $vuln_func and $vuln_file
}

Sigma Rule

title: Unauthenticated AJAX Access to Logger for Elementor
id: 8a9b3c4d-5e6f-7a8b-9c0d-1e2f3a4b5c6d
status: experimental
description: Detects unauthenticated POST requests to admin-ajax.php with logger actions
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
    service: access
detection:
    selection:
        cs-method: POST
        cs-uri-query|contains: admin-ajax.php
        cs-uri-query|contains|all:
            - action=logger_
    condition: selection
falsepositives:
    - Legitimate admin actions (rare)
level: high

Suricata Rule

alert http any any -> any any (
    msg:"CVE-2025-66146 - Logger for Elementor Unauthenticated AJAX Access";
    flow:to_server,established;
    content:"POST"; http_method;
    content:"admin-ajax.php"; http_uri;
    content:"action=logger_"; http_client_body;
    classtype:attempted-recon;
    sid:1000001;
    rev:1;
)

Remediation & Mitigation

Immediate Actions:

1. Disable the Plugin: Deactivate and delete the Logger for Elementor plugin until a patch is released.
2. Review Logs: Check for any unauthorized access to log data and rotate any exposed credentials.
3. Update WordPress: Ensure core, themes, and other plugins are up to date.

Long-term Mitigation:

• Monitor the vendor's website or WordPress plugin repository for a patched version (>= 1.1.0).
• Implement a Web Application Firewall (WAF) with rules to block unauthenticated AJAX requests to plugin-specific actions.
• Conduct a security audit of all plugins for similar missing authorization issues.

Patch Details: UNKNOWN / UNPATCHED. No official patch is available at this time.

Valters IT
DevSecOps & Cyber Threat Intelligence