MozDef/alerts/multiple_intel_hits_pyes.py

69 строки
3.3 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
# Jeff Bryner jbryner@mozilla.com
# Michal Purzynski <mpurzynski@mozilla.com>
from lib.alerttask import AlertTask
import pyes
class AlertMultipleIntelHits(AlertTask):
def main(self):
# look for events in last X mins
date_timedelta = dict(minutes=2)
# Configure filters using pyes
must = [
pyes.TermFilter('_type', 'bro'),
pyes.TermFilter('eventsource', 'nsm'),
pyes.TermFilter('category', 'brointel'),
pyes.ExistsFilter('seenindicator'),
pyes.QueryFilter(pyes.MatchQuery('hostname', 'sensor1 sensor2 sensor3', 'boolean'))
]
self.filtersManual(date_timedelta, must=must)
# Search aggregations on field 'seenindicator', keep X samples of events at most
self.searchEventsAggregated('details.seenindicator', samplesLimit=10)
# alert when >= X matching events in an aggregation
self.walkAggregations(threshold=10)
# 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 = ['nsm,bro,intel']
severity = 'NOTICE'
hostname = aggreg['events'][0]['_source']['hostname']
summary = '{0} {1} {2} on {3}'.format(aggreg['count'], hostname, ' Bro intel match for indicator:', aggreg['value'])
summary += ' sample hosts that hit it: '
for e in aggreg['events'][:3]:
if 'details' in e['_source'].keys() \
and 'sourceipaddress' in e['_source']['details'].keys() \
and 'seenwhere' in e['_source']['details'].keys():
interestingaddres = ''
# someone talking to a bad guy, I want to know who
# someone resolving bad guy's domain name, I want to know who
# bad guy talking to someone, I want to know to whom
if 'Conn::IN_RESP' in e['_source']['details']['seenwhere'] \
or 'HTTP::IN_HOST_HEADER' in e['_source']['details']['seenwhere'] \
or 'DNS::IN_REQUEST' in e['_source']['details']['seenwhere']:
interestingaddres = e['_source']['details']['sourceipaddress']
elif 'Conn::IN_ORIG' in e['_source']['details']['seenwhere'] \
or 'HTTP::IN_X_CLUSTER_CLIENT_IP_HEADER' in e['_source']['details']['seenwhere'] \
or 'HTTP::IN_X_FORWARDED_FOR_HEADER' in e['_source']['details']['seenwhere']:
interestingaddres = e['_source']['details']['destinationipaddress']
summary += '{0} in {1} '.format(interestingaddres, e['_source']['details']['seenwhere'])
# Create the alert object based on these properties
return self.createAlertDict(summary, category, tags, aggreg['events'], severity)