#!/usr/bin/env python3
"""
CVE-2025-65083 PoC - GoSign Desktop TLS Certificate Validation Bypass
This PoC demonstrates the concept of the vulnerability where GoSign Desktop
disables TLS certificate validation when configured with a proxy server.
Note: This is for educational and authorized testing purposes only.
"""
import socket
import ssl
import json
from datetime import datetime
def create_malicious_proxy_response():
"""
Simulate a malicious proxy server that performs MITM attack
"""
print("[*] Simulating malicious proxy server behavior...")
print("[*] In vulnerable GoSign Desktop, certificate validation would be disabled")
print("[*] This allows arbitrary certificates to be accepted")
# Simulate the vulnerable behavior
vulnerable_config = {
"proxy_enabled": True,
"certificate_verification": "SSL_VERIFY_NONE",
"security_impact": "Integrity protection bypassed",
"attack_vector": "Man-in-the-Middle (MITM)"
}
return vulnerable_config
def demonstrate_attack_scenario():
"""
Demonstrate the attack chain for exploiting this vulnerability
"""
attack_steps = [
{
"step": 1,
"action": "Attacker sets up malicious proxy server",
"description": "Attacker configures a proxy server under their control"
},
{
"step": 2,
"action": "Victim configures GoSign Desktop to use malicious proxy",
"description": "User unknowingly configures the software to use the attacker's proxy"
},
{
"step": 3,
"action": "GoSign Desktop disables certificate validation",
"description": "Due to vulnerability, TLS verification is set to SSL_VERIFY_NONE"
},
{
"step": 4,
"action": "Attacker performs MITM attack",
"description": "Attacker intercepts and can modify HTTPS traffic"
},
{
"step": 5,
"action": "Integrity protection bypassed",
"description": "Communication integrity is compromised"
}
]
return attack_steps
def check_vulnerability(product_name="GoSign Desktop", version="2.4.1"):
"""
Check if the product version is vulnerable
"""
print(f"[*] Checking vulnerability status for {product_name} v{version}")
# Known affected versions
affected_versions = ["2.4.1", "2.4.0", "2.3.x", "2.2.x", "2.1.x"]
if version in affected_versions or version.startswith("2."):
result = {
"vulnerable": True,
"product": product_name,
"version": version,
"reason": "Versions through 2.4.1 disable TLS cert validation with proxy"
}
else:
result = {
"vulnerable": False,
"product": product_name,
"version": version,
"recommendation": "Update to latest version"
}
return result
if __name__ == "__main__":
print("=" * 60)
print("CVE-2025-65083 PoC - GoSign Desktop TLS Bypass")
print("=" * 60)
# Demonstrate vulnerability
config = create_malicious_proxy_response()
print(f"\n[*] Vulnerable Configuration: {json.dumps(config, indent=2)}")
# Show attack chain
print("\n[*] Attack Chain:")
for step in demonstrate_attack_scenario():
print(f" Step {step['step']}: {step['action']}")
print(f" -> {step['description']}")
# Check vulnerability status
print("\n[*] Vulnerability Check:")
result = check_vulnerability()
print(json.dumps(result, indent=2))