misp-modules/misp_modules/modules/expansion/crowdstrike_falcon.py

139 lines
5.6 KiB
Python
Executable File

import json
from . import check_input_attribute, standard_error_message
from falconpy import Intel
from pymisp import MISPAttribute, MISPEvent
moduleinfo = {'version': '0.2',
'author': 'Christophe Vandeplas',
'description': 'Module to query CrowdStrike Falcon.',
'module-type': ['expansion', 'hover']}
moduleconfig = ['api_id', 'apikey']
misperrors = {'error': 'Error'}
misp_type_in = ['domain', 'email-attachment', 'email-dst', 'email-reply-to', 'email-src', 'email-subject',
'filename', 'hostname', 'ip', 'ip-src', 'ip-dst', 'md5', 'mutex', 'regkey', 'sha1', 'sha256', 'uri', 'url',
'user-agent', 'whois-registrant-email', 'x509-fingerprint-md5']
mapping_out = { # mapping between the MISP attributes type and the compatible CrowdStrike indicator types.
'domain': {'type': 'hostname', 'to_ids': True},
'email_address': {'type': 'email-src', 'to_ids': True},
'email_subject': {'type': 'email-subject', 'to_ids': True},
'file_name': {'type': 'filename', 'to_ids': True},
'hash_md5': {'type': 'md5', 'to_ids': True},
'hash_sha1': {'type': 'sha1', 'to_ids': True},
'hash_sha256': {'type': 'sha256', 'to_ids': True},
'ip_address': {'type': 'ip-dst', 'to_ids': True},
'ip_address_block': {'type': 'ip-dst', 'to_ids': True},
'mutex_name': {'type': 'mutex', 'to_ids': True},
'registry': {'type': 'regkey', 'to_ids': True},
'url': {'type': 'url', 'to_ids': True},
'user_agent': {'type': 'user-agent', 'to_ids': True},
'x509_serial': {'type': 'x509-fingerprint-md5', 'to_ids': True},
'actors': {'type': 'threat-actor', 'category': 'Attribution'},
'malware_families': {'type': 'text', 'category': 'Attribution'}
}
misp_type_out = [item['type'] for item in mapping_out.values()]
mispattributes = {'input': misp_type_in, 'format': 'misp_standard'}
def handler(q=False):
if q is False:
return False
request = json.loads(q)
#validate CrowdStrike params
if (request.get('config')):
if (request['config'].get('apikey') is None):
misperrors['error'] = 'CrowdStrike apikey is missing'
return misperrors
if (request['config'].get('api_id') is None):
misperrors['error'] = 'CrowdStrike api_id is missing'
return misperrors
#validate attribute
if not request.get('attribute') or not check_input_attribute(request['attribute']):
return {'error': f'{standard_error_message}, which should contain at least a type, a value and an uuid.'}
attribute = request.get('attribute')
if not any(input_type == attribute.get('type') for input_type in misp_type_in):
return {'error': 'Unsupported attribute type.'}
client = CSIntelAPI(request['config']['api_id'], request['config']['apikey'])
attribute = MISPAttribute()
attribute.from_dict(**request.get('attribute') )
r = {"results": []}
valid_type = False
try:
for k in misp_type_in:
if attribute.type == k:
# map the MISP type to the CrowdStrike type
r['results'].append(lookup_indicator(client, attribute))
valid_type = True
except Exception as e:
return {'error': f"{e}"}
if not valid_type:
misperrors['error'] = "Unsupported attributes type"
return misperrors
return {'results': r.get('results').pop()}
def lookup_indicator(client, ref_attribute):
result = client.search_indicator(ref_attribute.value)
misp_event = MISPEvent()
misp_event.add_attribute(**ref_attribute)
for item in result.get('resources', []):
for relation in item.get('relations'):
if mapping_out.get(relation.get('type')):
r = mapping_out[relation.get('type')].copy()
r['value'] = relation.get('indicator')
attribute = MISPAttribute()
attribute.from_dict(**r)
misp_event.add_attribute(**attribute)
for actor in item.get('actors'):
r = mapping_out.get('actors').copy()
r['value'] = actor
attribute = MISPAttribute()
attribute.from_dict(**r)
misp_event.add_attribute(**attribute)
if item.get('malware_families'):
r = mapping_out.get('malware_families').copy()
r['value'] = f"malware_families: {' | '.join(item.get('malware_families'))}"
attribute = MISPAttribute()
attribute.from_dict(**r)
misp_event.add_attribute(**attribute)
event = json.loads(misp_event.to_json())
return {'Object': event.get('Object', []), 'Attribute': event.get('Attribute', [])}
def introspection():
return mispattributes
def version():
moduleinfo['config'] = moduleconfig
return moduleinfo
class CSIntelAPI():
def __init__(self, custid=None, custkey=None):
# customer id and key should be passed when obj is created
self.falcon = Intel(client_id=custid, client_secret=custkey)
def search_indicator(self, query):
r = self.falcon.query_indicator_entities(q=query)
# 400 - bad request
if r.get('status_code') == 400:
raise Exception('HTTP Error 400 - Bad request.')
# 404 - oh shit
if r.get('status_code') == 404:
raise Exception('HTTP Error 404 - awww snap.')
# catch all?
if r.get('status_code') != 200:
raise Exception('HTTP Error: ' + str(r.get('status_code')))
if len(r.get('body').get('errors')):
raise Exception('API Error: ' + ' | '.join(r.get('body').get('errors')))
return r.get('body', {})