MozDef/alerts/duo_fail_open.py

44 строки
1.8 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
#
# This script alerts when openvpn's duo security failed to contact the duo server and let the user in.
# This is a very serious warning that must be acted upon as it means MFA failed and only one factor was validated (in
# this case a VPN certificate)
from lib.alerttask import AlertTask
from mozdef_util.query_models import SearchQuery, PhraseMatch
class AlertDuoFailOpen(AlertTask):
def main(self):
search_query = SearchQuery(minutes=15)
search_query.add_must(PhraseMatch('summary', 'Failsafe Duo login'))
self.filtersManual(search_query)
# Search aggregations on field 'sourceipaddress', keep X samples of
# events at most
self.searchEventsAggregated('hostname', samplesLimit=10)
# alert when >= X matching events in an aggregation
# in this case, always
self.walkAggregations(threshold=1)
# 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 = 'bypass'
tags = ['openvpn', 'duosecurity']
severity = 'WARNING'
summary = 'DuoSecurity contact failed, fail open triggered on {0}'.format(aggreg['value'])
# Create the alert object based on these properties
return self.createAlertDict(summary, category, tags, aggreg['events'], severity)