MozDef/alerts/bruteforce_ssh_pyes.py

53 строки
2.2 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
from lib.alerttask import AlertTask
import pyes
class AlertBruteforceSsh(AlertTask):
def main(self):
# look for events in last X mins
date_timedelta = dict(minutes=2)
# Configure filters using pyes
must = [
pyes.TermFilter('_type', 'event'),
pyes.QueryFilter(pyes.MatchQuery('summary','failed','phrase')),
pyes.TermFilter('program','sshd'),
pyes.QueryFilter(pyes.MatchQuery('summary', 'login invalid ldap_count_entries', 'boolean'))
]
must_not = [
pyes.QueryFilter(pyes.MatchQuery('summary','10.22.75.203','phrase')),
pyes.QueryFilter(pyes.MatchQuery('summary','10.8.75.144','phrase'))
]
self.filtersManual(date_timedelta, must=must, must_not=must_not)
# Search aggregations on field 'sourceipaddress', keep X samples of events at most
self.searchEventsAggregated('details.sourceipaddress', 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 = 'bruteforce'
tags = ['ssh']
severity = 'NOTICE'
summary = ('{0} ssh bruteforce attempts by {1}'.format(aggreg['count'], aggreg['value']))
hosts = self.mostCommon(aggreg['allevents'],'_source.details.hostname')
for i in hosts[:5]:
summary += ' {0} ({1} hits)'.format(i[0], i[1])
# Create the alert object based on these properties
return self.createAlertDict(summary, category, tags, aggreg['events'], severity)