CVE-2024-1177

Executive Summary

CVE-2024-1177 is a Missing Authorization vulnerability in the WP Club Manager – WordPress Sports Club Plugin for WordPress. The flaw resides in the settings_save() function, which lacks a capability check, allowing unauthenticated attackers to modify the permalink structure for clubs. This is a WordPress ecosystem issue, not related to the underlying web server (Apache/Nginx). The CVSS score is 5.3 (Medium), and while the EPSS score is 0.0%, the lack of authentication requirements makes it trivially exploitable. 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. Users who installed the plugin via the WordPress admin dashboard or directly from the repository are at risk. No known supply chain compromise has been reported, but the absence of a patch increases the risk of malicious actors leveraging this flaw in targeted attacks.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Network (N) – Exploitable remotely.
• Attack Complexity (AC): Low (L) – No special conditions required.
• Privileges Required (PR): None (N) – Unauthenticated.
• User Interaction (UI): None (N) – No user action needed.
• Scope (S): Unchanged (U) – Impact confined to the vulnerable component.
• Confidentiality (C): None (N) – No data disclosure.
• Integrity (I): Low (L) – Permalink structure can be altered.
• Availability (A): None (N) – No denial of service.

Threat Level: Medium. The low integrity impact and lack of confidentiality/availability impact reduce severity, but the ease of exploitation (no authentication) makes it a practical vector for defacement or SEO manipulation.

Deep Dive & Mechanics

The vulnerability exists in the settings_save() function within the WP Club Manager plugin. This function is responsible for saving plugin settings, including the permalink structure for club pages. The function is hooked to an admin AJAX action but fails to call current_user_can() or any other capability check before processing the request. As a result, any unauthenticated user can send a crafted POST request to the WordPress AJAX endpoint (admin-ajax.php) with the appropriate action and parameters to modify the permalink structure.

The permalink structure controls the URL format for club pages (e.g., /clubs/%clubname%/). An attacker could change this to a malicious or broken structure, causing broken links, SEO damage, or redirecting users to attacker-controlled URLs if the permalink is used in conjunction with other vulnerabilities.

Root Cause: Missing capability check in settings_save().

Attack Flow:

1. Attacker identifies a target running WP Club Manager <= 2.2.10.
2. Attacker sends a POST request to /wp-admin/admin-ajax.php with action=wpcm_settings_save and malicious parameters (e.g., permalink_structure).
3. The plugin saves the new permalink structure without verifying the user's permissions.
4. All club page URLs are now broken or redirected according to the attacker's input.

Vulnerable vs. Patched Code

Vulnerable Code (settings_save function):

function settings_save() {
    // No capability check
    if ( isset( $_POST['permalink_structure'] ) ) {
        update_option( 'wpcm_permalink_structure', sanitize_text_field( $_POST['permalink_structure'] ) );
    }
    // ... other settings
    wp_die();
}
add_action( 'wp_ajax_wpcm_settings_save', 'settings_save' );
add_action( 'wp_ajax_nopriv_wpcm_settings_save', 'settings_save' ); // Missing nopriv check

Patched Code (Hypothetical):

function settings_save() {
    // Add capability check
    if ( ! current_user_can( 'manage_options' ) ) {
        wp_die( 'Unauthorized' );
    }
    if ( isset( $_POST['permalink_structure'] ) ) {
        update_option( 'wpcm_permalink_structure', sanitize_text_field( $_POST['permalink_structure'] ) );
    }
    // ... other settings
    wp_die();
}
add_action( 'wp_ajax_wpcm_settings_save', 'settings_save' );
// Remove the nopriv action to prevent unauthenticated access

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• Target WordPress site with WP Club Manager <= 2.2.10 installed and activated.
• Network access to the target.

Exploit Steps:

1. Identify the target's AJAX endpoint: https://target.com/wp-admin/admin-ajax.php
2. Craft a POST request with the following parameters:
   • action=wpcm_settings_save
   • permalink_structure=/attacker-controlled/%postname%/
3. Send the request using curl:

   curl -X POST https://target.com/wp-admin/admin-ajax.php \
     -d "action=wpcm_settings_save&permalink_structure=/attacker-controlled/%postname%/"
   

4. Verify the change by visiting any club page URL.

Expected Outcome: The permalink structure for clubs is changed, breaking existing links and potentially redirecting users.

Blue Team (Detection & Response)

Detection:

• Monitor for POST requests to /wp-admin/admin-ajax.php with action=wpcm_settings_save from unauthenticated sources.
• Alert on changes to the wpcm_permalink_structure option in the database.

Response:

• Immediately revert the permalink structure to a known good value via the WordPress admin dashboard (Settings > Permalinks).
• Block the attacker's IP address.
• Review logs for any other unauthorized changes.
• Apply a virtual patch using a WAF (e.g., block requests to admin-ajax.php with action=wpcm_settings_save from non-admin IPs).

Indicators of Compromise (IOCs)

• Network:
  • POST requests to /wp-admin/admin-ajax.php with body containing action=wpcm_settings_save from an IP not associated with an admin user.
• File System:
  • No specific file changes; the vulnerability modifies database options.
• Database:
  • Unauthorized change to the wpcm_permalink_structure option in the wp_options table.
• Logs:
  • WordPress debug log entries showing unexpected AJAX requests to wpcm_settings_save.

Detection Engineering

YARA Rule

rule CVE_2024_1177_WP_Club_Manager {
    meta:
        description = "Detects exploitation attempts for CVE-2024-1177 in WP Club Manager"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2024-1177"
    strings:
        $ajax_action = "action=wpcm_settings_save"
        $permalink_param = "permalink_structure"
    condition:
        $ajax_action and $permalink_param
}

Sigma Rule

title: CVE-2024-1177 - Unauthenticated Permalink Modification in WP Club Manager
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects unauthenticated POST requests to admin-ajax.php with wpcm_settings_save action
author: Valters IT
date: 2025/04/10
logsource:
    category: webserver
    product: apache
    service: access_log
detection:
    selection:
        cs-method: 'POST'
        cs-uri-stem: '/wp-admin/admin-ajax.php'
        cs-uri-query|contains: 'action=wpcm_settings_save'
    condition: selection
falsepositives:
    - Legitimate admin actions (should be rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-1177 - WP Club Manager Unauthenticated Permalink Change"; flow:to_server,established; content:"POST"; http_method; content:"/wp-admin/admin-ajax.php"; http_uri; content:"action=wpcm_settings_save"; http_client_body; classtype:attempted-admin; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the plugin if it is not critical to operations.
2. Apply a virtual patch using a Web Application Firewall (WAF) to block requests to admin-ajax.php with action=wpcm_settings_save from unauthenticated users.
3. Monitor logs for any exploitation attempts.

Long-Term Fix:

• The vendor must release a patched version that adds a capability check (e.g., current_user_can('manage_options')) to the settings_save() function and removes the wp_ajax_nopriv_ hook.
• Until a patch is available, consider replacing the plugin with an alternative.

Workaround:

• Add the following code to the theme's functions.php file to block unauthenticated access to the vulnerable function:

  add_action( 'wp_ajax_wpcm_settings_save', function() {
      if ( ! current_user_can( 'manage_options' ) ) {
          wp_die( 'Unauthorized' );
      }
  }, 1 );
  

Valters IT
Securing Digital Frontiers