Cisco ASA/FTD WebVPN File-Handler Heap Buffer Overflow Exposure Scanner (CVE-2025-20333)

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import requests
import sys
import warnings
from urllib3.exceptions import InsecureRequestWarning

warnings.simplefilter("ignore", InsecureRequestWarning)

def test_cve_2025_20333(base_url):
    base_url = base_url.rstrip('/')
    
    # Primary vulnerable endpoint for CVE-2025-20333 (file upload handler)
    key_paths = [
        "/+CSCOE+/files/file_action.html",
        "/+CSCOE+/files/file_list.html",
        "/+CSCOE+/file.php",
    ]
    
    # Common bypass patterns (can be chained with CVE-2025-20362)
    bypass_patterns = [
        "",
        "/..",
        "/../",
        "/+CSCOE+/../+CSCOE+/",
        "/%2bCSCOE%2b/../%2bCSCOE%2b/",
        "/+CSCOE+/..;/",
    ]
    
    headers = {
        'User-Agent': 'Mozilla/5.0 (compatible; CVE-2025-20333-Scanner)',
        'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
    }
    
    print(f"[+] Testing {base_url} for CVE-2025-20333 (Buffer Overflow / RCE)")
    print("[+] This checks the file upload handler used in exploitation.\n")
    
    vulnerable_indicators = 0
    hits = []
    
    for base_path in key_paths:
        for bypass in bypass_patterns:
            try:
                test_url = base_url + base_path + bypass
                # Use GET first (safer)
                r = requests.get(
                    test_url,
                    headers=headers,
                    verify=False,
                    timeout=12,
                    allow_redirects=True
                )
                
                status = r.status_code
                length = len(r.text)
                
                print(f"  {status:3d} | {length:6d} bytes | {base_path}{bypass}")
                
                lower_text = r.text.lower()
                
                # Indicators that the endpoint is active/reachable
                if status == 200 and length > 300:
                    if any(kw in lower_text for kw in ["upload", "file", "action", "mode=", "path=", "webvpn"]):
                        print(f"    ⚠️  ENDPOINT REACHABLE - Potential attack surface for CVE-2025-20333")
                        vulnerable_indicators += 1
                        hits.append(test_url)
                
            except requests.exceptions.RequestException:
                continue
    
    # Summary
    if vulnerable_indicators >= 2:
        print("\n🚨 HIGH RISK: Key endpoints for CVE-2025-20333 are accessible.")
        print("   This vulnerability is a heap buffer overflow that can lead to RCE as root.")
        print("   Recommendation: Patch immediately + check for compromise.")
    elif vulnerable_indicators > 0:
        print("\n⚠️  Potential exposure to CVE-2025-20333 detected.")
    else:
        print("\n✅ No clear indicators of the vulnerable endpoint (may be patched or not exposed).")
    
    if hits:
        print("\nReachable endpoints:")
        for url in hits[:6]:
            print(f"   → {url}")

if __name__ == "__main__":
    if len(sys.argv) < 2:
        print("Usage: python cve_2025_20333_test.py https://target-vpn.example.com")
        sys.exit(1)
    
    test_cve_2025_20333(sys.argv[1])