import json import requests from . import check_input_attribute, standard_error_message from pymisp import MISPAttribute, MISPEvent, MISPObject misperrors = {'error': 'Error'} mispattributes = {'input': ['hostname', 'domain', "ip-src", "ip-dst", "md5", "sha1", "sha256", "url"], 'format': 'misp_standard'} # possible module-types: 'expansion', 'hover' or both moduleinfo = {'version': '4', 'author': 'Hannah Ward', 'description': 'Get information from VirusTotal', 'module-type': ['expansion']} # config fields that your code expects from the site admin moduleconfig = ["apikey", "event_limit"] class VirusTotalParser(object): def __init__(self, apikey, limit): self.apikey = apikey self.limit = limit self.base_url = "https://www.virustotal.com/vtapi/v2/{}/report" self.misp_event = MISPEvent() self.parsed_objects = {} self.input_types_mapping = {'ip-src': self.parse_ip, 'ip-dst': self.parse_ip, 'domain': self.parse_domain, 'hostname': self.parse_domain, 'md5': self.parse_hash, 'sha1': self.parse_hash, 'sha256': self.parse_hash, 'url': self.parse_url} def query_api(self, attribute): self.attribute = MISPAttribute() self.attribute.from_dict(**attribute) return self.input_types_mapping[self.attribute.type](self.attribute.value, recurse=True) def get_result(self): event = json.loads(self.misp_event.to_json()) results = {key: event[key] for key in ('Attribute', 'Object') if (key in event and event[key])} return {'results': results} ################################################################################ #### Main parsing functions #### # noqa ################################################################################ def parse_domain(self, domain, recurse=False): req = requests.get(self.base_url.format('domain'), params={'apikey': self.apikey, 'domain': domain}) if req.status_code != 200: return req.status_code req = req.json() hash_type = 'sha256' whois = 'whois' feature_types = {'communicating': 'communicates-with', 'downloaded': 'downloaded-from', 'referrer': 'referring'} siblings = (self.parse_siblings(domain) for domain in req['domain_siblings']) uuid = self.parse_resolutions(req['resolutions'], req['subdomains'] if 'subdomains' in req else None, siblings) for feature_type, relationship in feature_types.items(): for feature in ('undetected_{}_samples', 'detected_{}_samples'): for sample in req.get(feature.format(feature_type), [])[:self.limit]: status_code = self.parse_hash(sample[hash_type], False, uuid, relationship) if status_code != 200: return status_code if req.get(whois): whois_object = MISPObject(whois) whois_object.add_attribute('text', type='text', value=req[whois]) self.misp_event.add_object(**whois_object) return self.parse_related_urls(req, recurse, uuid) def parse_hash(self, sample, recurse=False, uuid=None, relationship=None): req = requests.get(self.base_url.format('file'), params={'apikey': self.apikey, 'resource': sample}) status_code = req.status_code if req.status_code == 200: req = req.json() vt_uuid = self.parse_vt_object(req) file_attributes = [] for hash_type in ('md5', 'sha1', 'sha256'): if req.get(hash_type): file_attributes.append({'type': hash_type, 'object_relation': hash_type, 'value': req[hash_type]}) if file_attributes: file_object = MISPObject('file') for attribute in file_attributes: file_object.add_attribute(**attribute) file_object.add_reference(vt_uuid, 'analyzed-with') if uuid and relationship: file_object.add_reference(uuid, relationship) self.misp_event.add_object(**file_object) return status_code def parse_ip(self, ip, recurse=False): req = requests.get(self.base_url.format('ip-address'), params={'apikey': self.apikey, 'ip': ip}) if req.status_code != 200: return req.status_code req = req.json() if req.get('asn'): asn_mapping = {'network': ('ip-src', 'subnet-announced'), 'country': ('text', 'country')} asn_object = MISPObject('asn') asn_object.add_attribute('asn', type='AS', value=req['asn']) for key, value in asn_mapping.items(): if req.get(key): attribute_type, relation = value asn_object.add_attribute(relation, type=attribute_type, value=req[key]) self.misp_event.add_object(**asn_object) uuid = self.parse_resolutions(req['resolutions']) if req.get('resolutions') else None return self.parse_related_urls(req, recurse, uuid) def parse_url(self, url, recurse=False, uuid=None): req = requests.get(self.base_url.format('url'), params={'apikey': self.apikey, 'resource': url}) status_code = req.status_code if req.status_code == 200: req = req.json() vt_uuid = self.parse_vt_object(req) if not recurse: feature = 'url' url_object = MISPObject(feature) url_object.add_attribute(feature, type=feature, value=url) url_object.add_reference(vt_uuid, 'analyzed-with') if uuid: url_object.add_reference(uuid, 'hosted-in') self.misp_event.add_object(**url_object) return status_code ################################################################################ #### Additional parsing functions #### # noqa ################################################################################ def parse_related_urls(self, query_result, recurse, uuid=None): if recurse: for feature in ('detected_urls', 'undetected_urls'): if feature in query_result: for url in query_result[feature]: value = url['url'] if isinstance(url, dict) else url[0] status_code = self.parse_url(value, False, uuid) if status_code != 200: return status_code else: for feature in ('detected_urls', 'undetected_urls'): if feature in query_result: for url in query_result[feature]: value = url['url'] if isinstance(url, dict) else url[0] self.misp_event.add_attribute('url', value) return 200 def parse_resolutions(self, resolutions, subdomains=None, uuids=None): domain_ip_object = MISPObject('domain-ip') if self.attribute.type in ('domain', 'hostname'): domain_ip_object.add_attribute('domain', type='domain', value=self.attribute.value) attribute_type, relation, key = ('ip-dst', 'ip', 'ip_address') else: domain_ip_object.add_attribute('ip', type='ip-dst', value=self.attribute.value) attribute_type, relation, key = ('domain', 'domain', 'hostname') for resolution in resolutions: domain_ip_object.add_attribute(relation, type=attribute_type, value=resolution[key]) if subdomains: for subdomain in subdomains: attribute = MISPAttribute() attribute.from_dict(**dict(type='domain', value=subdomain)) self.misp_event.add_attribute(**attribute) domain_ip_object.add_reference(attribute.uuid, 'subdomain') if uuids: for uuid in uuids: domain_ip_object.add_reference(uuid, 'sibling-of') self.misp_event.add_object(**domain_ip_object) return domain_ip_object.uuid def parse_siblings(self, domain): attribute = MISPAttribute() attribute.from_dict(**dict(type='domain', value=domain)) self.misp_event.add_attribute(**attribute) return attribute.uuid def parse_vt_object(self, query_result): if query_result['response_code'] == 1: vt_object = MISPObject('virustotal-report') vt_object.add_attribute('permalink', type='link', value=query_result['permalink']) detection_ratio = '{}/{}'.format(query_result['positives'], query_result['total']) vt_object.add_attribute('detection-ratio', type='text', value=detection_ratio, disable_correlation=True) self.misp_event.add_object(**vt_object) return vt_object.uuid def parse_error(status_code): status_mapping = {204: 'VirusTotal request rate limit exceeded.', 400: 'Incorrect request, please check the arguments.', 403: 'You don\'t have enough privileges to make the request.'} if status_code in status_mapping: return status_mapping[status_code] return "VirusTotal may not be accessible." def handler(q=False): if q is False: return False request = json.loads(q) if not request.get('config') or not request['config'].get('apikey'): misperrors['error'] = "A VirusTotal api key is required for this module." return misperrors 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.'} if request['attribute']['type'] not in mispattributes['input']: return {'error': 'Unsupported attribute type.'} event_limit = request['config'].get('event_limit') if not isinstance(event_limit, int): event_limit = 5 parser = VirusTotalParser(request['config']['apikey'], event_limit) attribute = request['attribute'] status = parser.query_api(attribute) if status != 200: misperrors['error'] = parse_error(status) return misperrors return parser.get_result() def introspection(): return mispattributes def version(): moduleinfo['config'] = moduleconfig return moduleinfo