CVE-2025-60106

Executive Summary

CVE-2025-60106 is a Missing Authorization vulnerability in the Roxnor EmailKit WordPress plugin, affecting versions from n/a through 1.6.0. This flaw allows an unauthenticated attacker to exploit incorrectly configured access control security levels, potentially leading to unauthorized data access or modification. The vulnerability is classified under CWE-862 (Missing Authorization) and has a CVSS score of 4.9 (Medium). As of the latest analysis, no patch is available, and no public proof-of-concept (PoC) or exploit code has been released. The EPSS score is 0.0%, indicating a low probability of exploitation in the wild, but the risk remains due to the lack of a patch.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed via the official WordPress plugin repository. Users are advised to monitor for updates from the vendor and consider disabling the plugin until a patch is released. No known supply chain attacks have been reported.

CVSS Breakdown & Threat Level

• CVSS Score: 4.9 (Medium)
• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
• Attack Vector: Network
• Attack Complexity: Low
• Privileges Required: None
• User Interaction: None
• Scope: Unchanged
• Confidentiality Impact: Low
• Integrity Impact: Low
• Availability Impact: None

The threat level is Medium due to the low complexity and no required privileges, but the impact is limited to low confidentiality and integrity loss.

Deep Dive & Mechanics

The vulnerability resides in the EmailKit plugin's access control mechanisms. The plugin fails to properly validate user permissions when processing certain API requests or administrative actions. This allows an unauthenticated attacker to bypass authorization checks and perform actions that should be restricted to authenticated users with specific roles.

Root Cause: The plugin uses current_user_can() checks inconsistently or not at all in some endpoints, leading to missing authorization. For example, an AJAX handler might be registered without a capability check, allowing any visitor to trigger it.

Attack Vector: An attacker can send crafted HTTP requests to the vulnerable endpoints, such as:

• POST /wp-admin/admin-ajax.php?action=emailkit_some_action
• GET /wp-json/emailkit/v1/some_endpoint

Impact: Successful exploitation could allow an attacker to:

• Read sensitive plugin configuration data.
• Modify plugin settings.
• Access or delete email logs.
• Potentially escalate privileges if combined with other vulnerabilities.

Vulnerable vs. Patched Code

Since no patch is available, the vulnerable code is the current state. A hypothetical patch would involve adding proper capability checks.

Vulnerable Code (Example):

add_action('wp_ajax_nopriv_emailkit_export_logs', 'emailkit_export_logs');
function emailkit_export_logs() {
    // No capability check
    $logs = get_option('emailkit_logs');
    echo json_encode($logs);
    wp_die();
}

Patched Code (Hypothetical):

add_action('wp_ajax_emailkit_export_logs', 'emailkit_export_logs');
function emailkit_export_logs() {
    if (!current_user_can('manage_options')) {
        wp_die('Unauthorized', 403);
    }
    $logs = get_option('emailkit_logs');
    echo json_encode($logs);
    wp_die();
}

Exploitation & Lab Setup

Red Team

Prerequisites:

• A WordPress site with EmailKit plugin version <= 1.6.0.
• Network access to the target.

Exploitation Steps:

1. Identify vulnerable endpoints by analyzing the plugin's source code or using fuzzing.
2. Send a crafted request to an unprotected AJAX handler:

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

3. If successful, the response will contain sensitive data.

Note: No public exploit code is available. The above is a hypothetical example.

Blue Team

Detection:

• Monitor for unusual AJAX requests to admin-ajax.php with actions prefixed by emailkit_ from unauthenticated users.
• Look for HTTP 200 responses to such requests without prior authentication.

Hunting:

• Search logs for patterns like action=emailkit_ in wp-admin/admin-ajax.php from IPs not in the allowed list.
• Use the Sigma rule below to detect unauthorized access attempts.

Indicators of Compromise (IOCs)

• Network:
  • HTTP requests to /wp-admin/admin-ajax.php with action=emailkit_* parameters from unauthenticated sources.
  • Unusual GET/POST requests to /wp-json/emailkit/v1/* endpoints.
• File:
  • Modified plugin files in /wp-content/plugins/emailkit/ (if attacker gains write access).
• Log:
  • Repeated 403 errors followed by 200 success on the same endpoint from the same IP.

Detection Engineering

YARA Rule

rule CVE_2025_60106_EmailKit_Missing_Auth {
    meta:
        description = "Detects missing authorization in EmailKit plugin files"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-60106"
    strings:
        $vuln1 = "wp_ajax_nopriv_emailkit" ascii wide nocase
        $vuln2 = "add_action('wp_ajax_nopriv_" ascii wide nocase
        $vuln3 = "current_user_can" ascii wide nocase
    condition:
        ($vuln1 or $vuln2) and not $vuln3
}

Sigma Rule

title: CVE-2025-60106 - EmailKit Missing Authorization Attempt
id: 8a4b3c2d-1e5f-4a7b-9c8d-0e1f2a3b4c5d
status: experimental
description: Detects attempts to exploit missing authorization in EmailKit plugin
author: Valters IT
date: 2025/04/10
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2025-60106
logsource:
    category: webserver
    product: apache
    service: access_combined
detection:
    selection:
        cs-method: 'POST'
        cs-uri-query|contains: 'action=emailkit_'
        sc-status: 200
    condition: selection
falsepositives:
    - Legitimate admin actions (if authenticated)
level: medium

Suricata Rule

alert http any any -> $HOME_NET any (
    msg:"CVE-2025-60106 - EmailKit Missing Authorization Attempt";
    flow:to_server,established;
    content:"POST"; http_method;
    content:"/wp-admin/admin-ajax.php"; http_uri;
    content:"action=emailkit_"; http_client_body;
    classtype:attempted-admin;
    sid:1000001;
    rev:1;
)

Remediation & Mitigation

Immediate Actions:

1. Disable the plugin until a patch is released.
2. Implement a Web Application Firewall (WAF) rule to block requests to admin-ajax.php with action=emailkit_* from unauthenticated users.
3. Monitor logs for exploitation attempts using the provided Sigma rule.

Long-term:

• Apply the vendor's patch once available.
• Conduct a security audit of all WordPress plugins.
• Enforce the principle of least privilege for all plugin functionalities.

Workaround:

• Add a custom capability check via a mu-plugin:

  add_action('init', function() {
      if (defined('DOING_AJAX') && DOING_AJAX) {
          if (strpos($_REQUEST['action'], 'emailkit_') === 0) {
              if (!current_user_can('manage_options')) {
                  wp_die('Unauthorized', 403);
              }
          }
      }
  });
  

Valters IT
Securing Digital Frontiers