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

176 lines
6.9 KiB
Python

import json
import requests
from . import check_input_attribute, standard_error_message
from collections import defaultdict
from pymisp import MISPAttribute, MISPEvent, MISPObject
misperrors = {'error': 'Error'}
mispattributes = {'input': ['vulnerability'], 'format': 'misp_standard'}
moduleinfo = {'version': '2', 'author': 'Christian Studer',
'description': 'An expansion module to enrich a CVE attribute with the vulnerability information.',
'module-type': ['expansion', 'hover']}
moduleconfig = ["custom_API"]
cveapi_url = 'https://cvepremium.circl.lu/api/'
class VulnerabilityParser():
def __init__(self, attribute, api_url):
misp_attribute = MISPAttribute()
misp_attribute.from_dict(**attribute)
misp_event = MISPEvent()
misp_event.add_attribute(**misp_attribute)
self.__misp_attribute = misp_attribute
self.__misp_event = misp_event
self.__api_url = api_url
self.references = defaultdict(list)
self.__capec_features = ('id', 'name', 'summary', 'prerequisites', 'solutions')
self.__vulnerability_mapping = {
'id': 'id', 'summary': 'summary',
'Modified': 'modified', 'cvss3': 'cvss-score',
'cvss3-vector': 'cvss-string'
}
self.__vulnerability_multiple_mapping = {
'vulnerable_configuration': 'vulnerable-configuration',
'vulnerable_configuration_cpe_2_2': 'vulnerable-configuration',
'references': 'references'
}
self.__weakness_mapping = {
'name': 'name', 'description_summary': 'description',
'status': 'status', 'weaknessabs': 'weakness-abs'
}
@property
def api_url(self) -> str:
return self.__api_url
@property
def capec_features(self) -> tuple:
return self.__capec_features
@property
def misp_attribute(self) -> MISPAttribute:
return self.__misp_attribute
@property
def misp_event(self) -> MISPEvent:
return self.__misp_event
@property
def vulnerability_mapping(self) -> dict:
return self.__vulnerability_mapping
@property
def vulnerability_multiple_mapping(self) -> dict:
return self.__vulnerability_multiple_mapping
@property
def weakness_mapping(self) -> dict:
return self.__weakness_mapping
def get_result(self):
if self.references:
self.__build_references()
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}
def parse_vulnerability_information(self, vulnerability):
vulnerability_object = MISPObject('vulnerability')
for feature, relation in self.vulnerability_mapping.items():
if vulnerability.get(feature):
vulnerability_object.add_attribute(relation, vulnerability[feature])
if 'Published' in vulnerability:
vulnerability_object.add_attribute('published', vulnerability['Published'])
vulnerability_object.add_attribute('state', 'Published')
for feature, relation in self.vulnerability_multiple_mapping.items():
if feature in vulnerability:
for value in vulnerability[feature]:
if isinstance(value, dict):
value = value['title']
vulnerability_object.add_attribute(relation, value)
vulnerability_object.add_reference(self.misp_attribute.uuid, 'related-to')
self.misp_event.add_object(vulnerability_object)
if 'cwe' in vulnerability and vulnerability['cwe'] not in ('Unknown', 'NVD-CWE-noinfo'):
self.__parse_weakness(vulnerability['cwe'], vulnerability_object.uuid)
if 'capec' in vulnerability:
self.__parse_capec(vulnerability['capec'], vulnerability_object.uuid)
def __build_references(self):
for object_uuid, references in self.references.items():
for misp_object in self.misp_event.objects:
if misp_object.uuid == object_uuid:
for reference in references:
misp_object.add_reference(**reference)
break
def __parse_capec(self, capec_values, vulnerability_uuid):
for capec in capec_values:
capec_object = MISPObject('attack-pattern')
for feature in self.capec_features:
capec_object.add_attribute(feature, capec[feature])
for related_weakness in capec['related_weakness']:
capec_object.add_attribute('related-weakness', f"CWE-{related_weakness}")
self.misp_event.add_object(capec_object)
self.references[vulnerability_uuid].append(
{
'referenced_uuid': capec_object.uuid,
'relationship_type': 'targeted-by'
}
)
def __parse_weakness(self, cwe_value, vulnerability_uuid):
cwe_string, cwe_id = cwe_value.split('-')[:2]
cwe = requests.get(f'{self.api_url}cwe/{cwe_id}')
if cwe.status_code == 200:
cwe = cwe.json()
weakness_object = MISPObject('weakness')
weakness_object.add_attribute('id', f'{cwe_string}-{cwe_id}')
for feature, relation in self.weakness_mapping.items():
if cwe.get(feature):
weakness_object.add_attribute(relation, cwe[feature])
self.misp_event.add_object(weakness_object)
self.references[vulnerability_uuid].append(
{
'referenced_uuid': weakness_object.uuid,
'relationship_type': 'weakened-by'
}
)
def check_url(url):
return f"{url}/" if not url.endswith('/') else url
def handler(q=False):
if q is False:
return False
request = json.loads(q)
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['attribute']
if attribute.get('type') != 'vulnerability':
misperrors['error'] = 'Vulnerability id missing.'
return misperrors
api_url = check_url(request['config']['custom_API']) if request.get('config', {}).get('custom_API') else cveapi_url
r = requests.get(f"{api_url}cve/{attribute['value']}")
if r.status_code == 200:
vulnerability = r.json()
if not vulnerability:
misperrors['error'] = 'Non existing CVE'
return misperrors['error']
else:
misperrors['error'] = 'API not accessible'
return misperrors['error']
parser = VulnerabilityParser(attribute, api_url)
parser.parse_vulnerability_information(vulnerability)
return parser.get_result()
def introspection():
return mispattributes
def version():
moduleinfo['config'] = moduleconfig
return moduleinfo