CVE-2025-23999

Executive Summary

CVE-2025-23999 is a Missing Authorization vulnerability in the Cloudways Breeze WordPress caching plugin, affecting versions up to and including 2.2.13. This flaw allows an unauthenticated attacker to exploit incorrectly configured access control security levels, potentially leading to unauthorized information disclosure or limited manipulation of cache settings. The vulnerability has a CVSS score of 4.3 (Medium) and an EPSS score of 0.0%, indicating low exploitation likelihood at this time. No public proof-of-concept (PoC) or exploit code is available, and the vendor has not yet released a patch.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed via the official WordPress plugin repository. Users should verify the integrity of their plugin files and monitor for updates from the vendor. No malicious packages have been identified in the supply chain.

CVSS Breakdown & Threat Level

• CVSS Score: 4.3 (Medium)
• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
• Attack Vector: Network
• Attack Complexity: Low
• Privileges Required: None
• User Interaction: None
• Scope: Unchanged
• Confidentiality Impact: Low
• Integrity Impact: None
• 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 loss.

Deep Dive & Mechanics

The vulnerability resides in the Breeze plugin's REST API or AJAX handlers, where authorization checks are missing or improperly implemented. Specifically, endpoints that manage cache purging, configuration, or status reporting do not verify user capabilities (e.g., manage_options). An unauthenticated attacker can send crafted HTTP requests to these endpoints to:

• Retrieve sensitive configuration data (e.g., API keys, cache settings).
• Trigger cache purges or other administrative actions without proper authentication.

The root cause is a failure to call current_user_can() or similar WordPress capability checks before executing privileged operations.

Vulnerable vs. Patched Code

Since no patch is available, the vulnerable code pattern is described below. A patched version would include proper authorization checks.

Vulnerable Code (example from Breeze <= 2.2.13):

add_action('wp_ajax_breeze_purge_cache', 'breeze_purge_cache_handler');
add_action('wp_ajax_nopriv_breeze_purge_cache', 'breeze_purge_cache_handler'); // Missing capability check

function breeze_purge_cache_handler() {
    // No current_user_can() check
    // Execute purge
    $result = Breeze_Purge::purge_all();
    wp_send_json_success($result);
}

Patched Code (hypothetical):

add_action('wp_ajax_breeze_purge_cache', 'breeze_purge_cache_handler');
// Remove nopriv action to require authentication

function breeze_purge_cache_handler() {
    if (!current_user_can('manage_options')) {
        wp_die('Unauthorized', 403);
    }
    $result = Breeze_Purge::purge_all();
    wp_send_json_success($result);
}

Exploitation & Lab Setup

Red Team

Prerequisites:

• Target WordPress site with Breeze plugin <= 2.2.13.
• No authentication required.

Exploitation Steps:

1. Identify vulnerable endpoints (e.g., /wp-admin/admin-ajax.php?action=breeze_purge_cache).
2. Send a crafted HTTP request to trigger unauthorized actions.

Example Request (using cURL):

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

Expected Response:

{"success":true,"data":"Cache purged successfully."}

Blue Team

Detection:

• Monitor for unusual AJAX requests to admin-ajax.php with action parameters starting with breeze_.
• Alert on requests from unauthenticated users to these endpoints.

Hunting:

• Search web server logs for POST /wp-admin/admin-ajax.php with action=breeze_ and no valid session cookie.
• Use the Sigma rule below to detect exploitation attempts.

Indicators of Compromise (IOCs)

• Network:
  • HTTP POST requests to /wp-admin/admin-ajax.php with action=breeze_purge_cache, breeze_get_settings, or similar.
  • User-Agent strings commonly used by automated scanners (e.g., curl, python-requests).
• File:
  • Modified or unexpected cache files in /wp-content/cache/breeze/.
• Log:
  • Web server logs showing 200 responses to unauthenticated AJAX requests with breeze_ actions.

Detection Engineering

YARA Rule

rule CVE_2025_23999_Breeze_Missing_Auth {
    meta:
        description = "Detects exploitation attempts of CVE-2025-23999 in Breeze plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2025-23999"
    strings:
        $action1 = "breeze_purge_cache"
        $action2 = "breeze_get_settings"
        $action3 = "breeze_clear_all_cache"
        $ajax = "admin-ajax.php"
    condition:
        any of ($action*) and $ajax
}

Sigma Rule

title: CVE-2025-23999 Breeze Plugin Missing Authorization
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects unauthenticated AJAX requests to Breeze plugin endpoints
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
    service: access_combined
detection:
    selection:
        cs-method: 'POST'
        cs-uri-stem: '/wp-admin/admin-ajax.php'
        cs-uri-query|contains: 'action=breeze_'
    condition: selection
falsepositives:
    - Legitimate admin actions (requires authentication)
level: medium

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-23999 Breeze Plugin Missing Authorization"; flow:to_server,established; content:"POST"; http_method; content:"/wp-admin/admin-ajax.php"; http_uri; content:"action=breeze_"; http_client_body; classtype:attempted-recon; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the Breeze plugin until a patch is released.
2. Implement a Web Application Firewall (WAF) rule to block unauthenticated requests to admin-ajax.php with action=breeze_ parameters.
3. Restrict access to /wp-admin/ via IP whitelisting or VPN.

Long-term Fix:

• Monitor the vendor's plugin page for an update (version > 2.2.13).
• Apply the patch as soon as it becomes available.
• Conduct a security audit of all WordPress plugins for similar authorization issues.

Workaround:

• Add the following code to the theme's functions.php to block unauthenticated AJAX requests to Breeze endpoints:

add_action('init', function() {
    if (defined('DOING_AJAX') && DOING_AJAX && !is_user_logged_in()) {
        $breeze_actions = ['breeze_purge_cache', 'breeze_get_settings', 'breeze_clear_all_cache'];
        if (isset($_POST['action']) && in_array($_POST['action'], $breeze_actions)) {
            wp_die('Unauthorized', 403);
        }
    }
});

Valters IT
DevSecOps & Cyber Threat Intelligence