MozDef/alerts/bro_intel_pyes.py

49 строки
1.9 KiB
Python

#!/usr/bin/env python
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
# Copyright (c) 2014 Mozilla Corporation
#
# Contributors:
# Anthony Verez averez@mozilla.com
from lib.alerttask import AlertTask
import pyes
class AlertBroIntel(AlertTask):
def main(self):
# look for events in last 30 mins
date_timedelta = dict(minutes=30)
# Configure filters using pyes
must = [
pyes.TermFilter('_type', 'event'),
pyes.TermFilter('category', 'brointel'),
pyes.ExistsFilter('seenindicator')
]
self.filtersManual(date_timedelta, must=must)
# Search aggregations on field 'seenindicator', keep 50 samples of events at most
self.searchEventsAggregated('details.seenindicator', samplesLimit=50)
# alert when >= 5 matching events in an aggregation
self.walkAggregations(threshold=5)
# Set alert properties
def onAggregation(self, aggreg):
# aggreg['count']: number of items in the aggregation, ex: number of failed login attempts
# aggreg['value']: value of the aggregation field, ex: toto@example.com
# aggreg['events']: list of events in the aggregation
category = 'bro'
tags = ['bro']
severity = 'NOTICE'
summary = ('{0} {1}: {2}'.format(aggreg['count'], 'bro intel match', aggreg['value']))
# append first 3 source IPs
summary += ' sample sourceips: '
for e in aggreg['events'][:3]:
if 'sourceipaddress' in e['_source']['details'].keys():
summary += '{0} '.format(e['_source']['details']['sourceipaddress'])
# Create the alert object based on these properties
return self.createAlertDict(summary, category, tags, aggreg['events'], severity)