CVE-2025-62946

Executive Summary

CVE-2025-62946 is a Missing Authorization vulnerability in the Everest Backup WordPress plugin, developed by Everestthemes. This flaw allows an unauthenticated attacker to exploit incorrectly configured access control security levels, potentially leading to unauthorized data access or manipulation. The vulnerability affects all versions up to and including 2.3.8. As of this report, no official patch has been released, and no public proof-of-concept (PoC) code is available. The CVSS score of 5.3 (Medium) reflects the potential for confidentiality impact without requiring authentication, but the lack of public exploits and low EPSS score (0.0%) suggests limited active exploitation in the wild.

Supply Chain & Package Security

This vulnerability is specific to the WordPress ecosystem as a plugin. It is not an NPM, PyPI, Go, or Ruby package. The risk is primarily to WordPress sites using the Everest Backup plugin, where an attacker could exploit missing authorization checks to access backup files or configuration data.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
• Base Score: 5.3 (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: None (I:N) – No data modification.
• Availability Impact: None (A:N) – No denial of service.

Threat Level: Medium. The vulnerability is easy to exploit remotely without authentication, but the impact is limited to low confidentiality. The lack of public exploits and low EPSS score reduces immediate risk, but unpatched installations remain vulnerable.

Deep Dive & Mechanics

The Everest Backup plugin for WordPress provides backup and restore functionality. The vulnerability stems from missing authorization checks in one or more REST API endpoints or AJAX actions. Specifically, the plugin fails to verify user capabilities (e.g., manage_options or export) before allowing access to backup-related operations. This allows any unauthenticated visitor to:

• List available backups.
• Download backup files containing sensitive data (e.g., database dumps, file archives).
• Potentially trigger backup or restore actions.

The flaw is classified under CWE-862: Missing Authorization, meaning the software does not perform any authorization check when accessing a resource or performing an action. In the context of WordPress, this typically involves missing current_user_can() checks in functions hooked to wp_ajax_* or wp_ajax_nopriv_* actions, or missing capability checks in REST API routes.

Vulnerable vs. Patched Code

Since no official patch is available, the vulnerable code is presumed to be in the plugin's core files. A typical vulnerable pattern in WordPress plugins is:

Vulnerable Code (example):

add_action('wp_ajax_nopriv_everest_backup_download', 'everest_backup_download_handler');
function everest_backup_download_handler() {
    // No capability check
    $backup_file = $_GET['file'];
    // Serve file without authorization
    header('Content-Type: application/octet-stream');
    readfile($backup_file);
    exit;
}

Patched Code (hypothetical):

add_action('wp_ajax_everest_backup_download', 'everest_backup_download_handler');
add_action('wp_ajax_nopriv_everest_backup_download', 'everest_backup_download_handler');
function everest_backup_download_handler() {
    // Add capability check
    if (!current_user_can('manage_options')) {
        wp_die('Unauthorized', 403);
    }
    $backup_file = $_GET['file'];
    // Serve file with authorization
    header('Content-Type: application/octet-stream');
    readfile($backup_file);
    exit;
}

The patched version would restrict access to authenticated users with the manage_options capability (typically administrators). Without a patch, all users (including unauthenticated) can access the functionality.

Exploitation & Lab Setup

Red Team

Objective: Exploit the missing authorization to download backup files.

Prerequisites:

• A WordPress site with Everest Backup plugin version <= 2.3.8.
• Network access to the target.

Exploitation Steps:

1. Identify the vulnerable endpoint. Common patterns include:
   • /wp-admin/admin-ajax.php?action=everest_backup_download&file=backup.zip
   • /wp-json/everest-backup/v1/backups
2. Send a direct request to the endpoint without authentication:

   curl -v "http://target.com/wp-admin/admin-ajax.php?action=everest_backup_download&file=backup_2025-01-01.zip"
   

3. If successful, the server will return the backup file. Analyze the file for sensitive data (database credentials, user data, etc.).

Note: No public exploit code is available, so this is based on common patterns.

Blue Team

Detection Steps:

1. Monitor for unusual access to admin-ajax.php or REST API endpoints without authentication.
2. Look for requests to download backup files (e.g., .zip, .sql, .tar.gz) from unauthenticated users.
3. Check server logs for 403 errors on backup endpoints (if patched) or successful downloads from unknown IPs.

Hunting Query (Splunk):

index=web sourcetype=access_combined
uri="/wp-admin/admin-ajax.php" action=everest_backup_download
| stats count by src_ip, uri, status
| where status=200

Indicators of Compromise (IOCs)

• Network IOCs:

  • HTTP requests to /wp-admin/admin-ajax.php with action=everest_backup_download parameter.
  • HTTP requests to /wp-json/everest-backup/v1/backups (if REST API is used).
  • Unusual download of .zip, .sql, or .tar.gz files from the WordPress installation.

• File IOCs:

  • Backup files accessed outside of normal administrative activity.
  • Presence of backup files in publicly accessible directories (e.g., /wp-content/uploads/everest-backup/).

• Log IOCs:

  • Repeated 200 responses to backup download requests from unauthenticated IPs.
  • Missing current_user_can() calls in plugin code (static analysis).

Detection Engineering

YARA Rule

rule CVE_2025_62946_Everest_Backup_Missing_Auth {
    meta:
        description = "Detects missing authorization in Everest Backup plugin"
        author = "Valters IT"
        date = "2025-04-10"
        cve = "CVE-2025-62946"
    strings:
        $func1 = "wp_ajax_nopriv_everest_backup" ascii wide nocase
        $func2 = "wp_ajax_everest_backup" ascii wide nocase
        $no_check = "current_user_can" ascii wide nocase
    condition:
        ($func1 or $func2) and not $no_check
}

Sigma Rule

title: CVE-2025-62946 - Everest Backup Missing Authorization
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects unauthenticated access to Everest Backup plugin endpoints
author: Valters IT
date: 2025/04/10
logsource:
    category: webserver
    product: apache
    service: access
detection:
    selection:
        cs-uri-query|contains: 
            - "action=everest_backup_download"
            - "everest-backup/v1/backups"
    condition: selection
falsepositives:
    - Legitimate admin access from authenticated users
level: medium

Suricata Rule

alert http any any -> $HOME_NET any (
    msg:"CVE-2025-62946 - Everest Backup Missing Authorization Attempt";
    flow:to_server,established;
    content:"/wp-admin/admin-ajax.php";
    http_uri;
    content:"action=everest_backup_download";
    http_uri;
    classtype:attempted-recon;
    sid:10000001;
    rev:1;
    priority:2;
)

Remediation & Mitigation

Immediate Actions:

1. Disable the plugin until an official patch is released. This is the most effective mitigation.
2. If disabling is not possible, restrict access to the plugin's endpoints using a Web Application Firewall (WAF) or server-level rules (e.g., .htaccess):

   <FilesMatch "admin-ajax\.php">
       Require all denied
       Require ip 127.0.0.1
   </FilesMatch>
   

3. Monitor logs for unauthorized access attempts.

Long-term Fix:

• Apply the official patch once released by Everestthemes.
• Implement a WordPress security plugin (e.g., Wordfence, Sucuri) to add virtual patching.
• Regularly update all plugins and themes.

Workaround Code (if you must keep the plugin): Add a capability check to the plugin's functions (requires code modification):

add_action('wp_ajax_nopriv_everest_backup_download', function() {
    if (!current_user_can('manage_options')) {
        wp_die('Unauthorized', 403);
    }
    // Original handler code here
}, 1);

Valters IT
Securing Digital Frontiers