add data exfiltration detection rule

This commit is contained in:
SofianeElNaggar
2024-11-20 16:47:15 -05:00
parent a1dcee53a1
commit e19b197acc

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@ -0,0 +1,50 @@
from collections import defaultdict
from scapy.all import IP
import time
data_transfer = defaultdict(lambda: {"current": 0, "daily": 0, "last_reset": time.time()})
def rule(packet, _, db):
"""Règle pour détecter une exfiltration de données importantes."""
global data_transfer
if IP in packet:
src_ip = packet[IP].src
dst_ip = packet[IP].dst
payload_size = len(packet[IP].payload)
# Mettre à jour le volume de données transférées
current_time = time.time()
if current_time - data_transfer[src_ip]["last_reset"] > rule.reset_time:
data_transfer[src_ip]["daily"] = 0
data_transfer[src_ip]["last_reset"] = current_time
data_transfer[src_ip]["current"] += payload_size
data_transfer[src_ip]["daily"] += payload_size
# Déclencher une alerte si un seuil est atteint
if data_transfer[src_ip]["current"] > rule.seuil_session:
alert = {
"type": "Exfiltration de données détectée (instantané)",
"source_ip": src_ip,
"destination_ip": dst_ip,
"volume": data_transfer[src_ip]["current"] / (1024 ** 3),
"threshold": rule.seuil_session / (1024 ** 3),
"time": time.strftime("%Y-%m-%d %H:%M:%S", time.gmtime()),
}
db.save_alert(alert)
data_transfer[src_ip]["current"] = 0 # Réinitialiser pour les prochaines sessions
if data_transfer[src_ip]["daily"] > rule.seuil_journalier:
alert = {
"type": "Exfiltration de données détectée (journalière)",
"source_ip": src_ip,
"volume": data_transfer[src_ip]["daily"] / (1024 ** 3),
"threshold": rule.seuil_journalier / (1024 ** 3),
"time": time.strftime("%Y-%m-%d %H:%M:%S", time.gmtime()),
}
db.save_alert(alert)
rule.reset_time = 24 * 3600 # 24 heures en secondes
rule.seuil_session = 5 * 1024 * 1024 * 1024 # 5 Go en octets
rule.seuil_journalier = 50 * 1024 * 1024 * 1024 # 50 Go en octets