def generate(): """parse the STIX on MITRE/CTI and return a layer dict with techniques with randomized scores""" # import the STIX data from MITRE/CTI stix = requests.get( "https://raw.githubusercontent.com/mitre/cti/master/enterprise-attack/enterprise-attack.json" ).json() ms = MemoryStore(stix_data=stix["objects"]) # get all techniques in STIX techniques = ms.query([Filter("type", "=", "attack-pattern")]) # parse techniques into layer format techniques_list = [] for technique in techniques: # skip deprecated and revoked if ("x_mitre_deprecated" in technique and technique["x_mitre_deprecated"]) or ("revoked" in technique and technique["revoked"]): continue techniqueID = technique["external_references"][0][ "external_id"] # get the attackID techniques_list.append({ "techniqueID": techniqueID, "score": random.randint(1, 100) # random score }) # return the techniques in a layer dict return { "name": "heatmap example", "version": "3.0", "sorting": 3, # descending order of score "description": "An example layer where all techniques have a randomized score", "domain": "mitre-enterprise", "techniques": techniques_list, }
def add_software(client, attack: MemoryStore, output_format: Text = "json") -> List[stix2.AttackPattern]: """ extract objects/facts related to ATT&CK Software Insert to ACT if client.baseurl is set, if not, print to stdout Args: attack (stix2): Stix attack instance """ notify = [] for software in attack.query([Filter("type", "in", ["tool", "malware"])]): tool_name = software.name.lower() # Tool category handle_fact(client.fact("category", software.type).source("tool", tool_name), output_format=output_format) if getattr(software, "revoked", None): # Object is revoked, add to notification list but do not add to facts that should be added to the platform notify.append(software) continue if getattr(software, "x_mitre_deprecated", None): # Object is revoked, add to notification list AND continue to add to facts that should be added to the platform notify.append(software) for alias in getattr(software, "x_mitre_aliases", []): if tool_name != alias.lower(): # Tool category (alias) handle_fact(client.fact("category", software.type).source( "tool", alias.lower()), output_format=output_format) handle_fact(client.fact("alias").bidirectional( "tool", tool_name, "tool", alias.lower()), output_format=output_format) # ATT&CK concept STIX Properties # ========================================================================== # Technqiues relationship where relationship_type == "uses", points to # a target object with type == "attack-pattern" for technique in attack.related_to(software, relationship_type="uses"): if technique.type != "attack-pattern": continue handle_fact(client.fact("implements").source( "tool", software.name.lower()).destination("technique", technique.name), output_format=output_format) return notify
def __init__(self, name=None, parentApp=None, framed=None, help=None, color='FORMDEFAULT', widget_list=None, cycle_widgets=False, *args, store: stix2.MemoryStore, **keywords): indicators = store.query([stix2.Filter('type', '=', 'indicator')]) self._provided_indicators = tuple(indicators) super().__init__(name, parentApp, framed, help, color, widget_list, cycle_widgets, *args, **keywords)
def add_techniques(client, attack: MemoryStore, output_format: Text = "json") -> List[stix2.AttackPattern]: """ extract objects/facts related to ATT&CK techniques Args: attack (stix2): Stix attack instance """ notify = [] # ATT&CK concept STIX Object type ACT object # ========================================================= # Technique attack-pattern technique # Filter out ATT&CK techniques (attack-pattern) from bundle for technique in attack.query([Filter("type", "=", "attack-pattern")]): if getattr(technique, "revoked", None): # Object is revoked, add to notification list but do not add to facts that should be added to the platform notify.append(technique) continue if getattr(technique, "x_mitre_deprecated", None): # Object is revoked, add to notification list AND continue to add to facts that should be added to the platform notify.append(technique) # Mitre ATT&CK Tactics are implemented in STIX as kill chain phases with kill_chain_name "mitre-attack" for tactic in technique.kill_chain_phases: if tactic.kill_chain_name != "mitre-attack": continue handle_fact(client.fact("accomplishes").source( "technique", technique.name).destination("tactic", tactic.phase_name), output_format=output_format) return notify
def generate(): """parse the STIX on MITRE/CTI and return a layer dict showing all techniques used by an APT group with phrase 'bear' in the group aliases.""" # import the STIX data from MITRE/CTI stix = requests.get( "https://raw.githubusercontent.com/mitre/cti/master/enterprise-attack/enterprise-attack.json" ).json() ms = MemoryStore(stix_data=stix["objects"]) groups = ms.query([Filter("type", "=", "intrusion-set")]) # find bear groups bear_groups = [] #list of groups with bear in name for group in groups: # filter out deprecated and revoked groups if ("x_mitre_deprecated" in group and group["x_mitre_deprecated"]) or ("revoked" in group and group["revoked"]): continue # check all aliases for bear for alias in group["aliases"]: if re.match(".*bear.*", alias, re.IGNORECASE) is not None: bear_groups.append(group) break # don't match the same group multiple times # find techniques used by bear groups techniques_used = {} #attackID => using bear groups for bear in bear_groups: # construct the "bear" name for the comment # if bear occurs in multiple aliases, list them all bearnames = [] for alias in bear["aliases"]: if re.match(".*bear.*", alias, re.IGNORECASE) is not None: bearnames.append(alias) bearname = bearnames[0] if len(bearnames) > 1: bearname += " (AKA " + ",".join(bearnames[1:]) + ")" # get techniques used by this group relationships = ms.relationships(bear["id"]) for relationship in relationships: # skip all non-technique relationships if "attack-pattern" not in relationship["target_ref"]: continue technique = ms.get(relationship["target_ref"]) # filter out deprecated and revoked techniques if ("x_mitre_deprecated" in technique and technique["x_mitre_deprecated"]) or ( "revoked" in technique and technique["revoked"]): continue techniqueID = technique["external_references"][0]["external_id"] # store usage in techniques_used struct if techniqueID in techniques_used: techniques_used[techniqueID].append(bearname) else: techniques_used[techniqueID] = [bearname] # format the techniques for the output layer techniques_list = [] for techniqueID in techniques_used: techniques_list.append({ "techniqueID": techniqueID, "comment": "used by " + ", ".join(techniques_used[techniqueID]), "color": "#ff6666" }) # construct and return the layer as a dict return { "name": "*Bear APTs", "versions": { "layer": "4.1", "navigator": "4.1" }, "description": "All techniques used by an APT group with phrase 'bear' in the group aliases", "domain": "enterprise-attack", "techniques": techniques_list, "legendItems": [{ "label": "Used by a group the phrase 'bear' in the group aliases", "color": "#ff6666" }] }
def generate(softwaretype="software"): """ generate and return a layer dict showing techniques used by software If softwaretype is specified as "malware" or "tool", only shows software of that type. If softwaretype is specified as "software" output layer shows both malware and tools """ # import the STIX data from MITRE/CTI stix = requests.get( "https://raw.githubusercontent.com/mitre/cti/master/enterprise-attack/enterprise-attack.json" ).json() ms = MemoryStore(stix_data=stix["objects"]) # software includes malware and tool types so perform two queries and merge the results software_filters = [] if softwaretype == "malware" or softwaretype == "software": software_filters.append([Filter('type', '=', 'malware')]) if softwaretype == "tool" or softwaretype == "software": software_filters.append([Filter('type', '=', 'tool')]) software = list(chain.from_iterable(ms.query(f) for f in software_filters)) # build a list of techniques used by software techniques_used = {} #attackID => using software names for thesoftware in software: # filter out revoked and deprecated software if ("x_mitre_deprecated" in thesoftware and thesoftware["x_mitre_deprecated"]) or ( "revoked" in thesoftware and thesoftware["revoked"]): continue for relationship in ms.relationships(thesoftware["id"]): # skip all non-technique relationships if "attack-pattern" not in relationship["target_ref"]: continue technique = ms.get(relationship["target_ref"]) # filter out deprecated and revoked techniques if ("x_mitre_deprecated" in technique and technique["x_mitre_deprecated"]) or ( "revoked" in technique and technique["revoked"]): continue techniqueID = technique["external_references"][0]["external_id"] # store usage in techniques_used struct if techniqueID in techniques_used: techniques_used[techniqueID].append(thesoftware["name"]) else: techniques_used[techniqueID] = [thesoftware["name"]] # format the techniques for the output layer techniques_list = [] highest_usage = 0 lowest_usage = 1 for techniqueID in techniques_used: # determine the number of used techniques for the score count = len(techniques_used[techniqueID]) highest_usage = max(highest_usage, count) lowest_usage = min(lowest_usage, count) # append technique struct to list of layer-formatted techniques techniques_list.append({ "techniqueID": techniqueID, "comment": "executed by " + ", ".join(techniques_used[techniqueID]), "score": count, }) # set up layer name and desc according to softwaretype if softwaretype != "software": plural = "tools" if softwaretype == "tool" else "malware" layername = f"Software ({softwaretype}) Execution" layerdescription = f"All techniques that can be executed by software of subtype {softwaretype}, where the score is the count of {plural} using the technique" else: layername = "Software Execution" layerdescription = f"All techniques that can be executed by software, where the score is the count of software using the technique" # construct and return the layer as a dict return { "name": layername, "description": layerdescription, "version": "3.0", "domain": "mitre-enterprise", "techniques": techniques_list, "sorting": 3, # order in descending order of score (count) "gradient": { "colors": [ "#fff7b3", # low counts are yellow "#ff6666", # high counts are red ], "minValue": lowest_usage, "maxValue": highest_usage }, }
def add_groups(client, attack: MemoryStore, output_format: Text = "json") -> List[stix2.AttackPattern]: """ extract objects/facts related to ATT&CK Groups Args: attack (stix2): Stix attack instance """ notify = [] # ATT&CK concept STIX Object type ACT object # ========================================================= # Group intrusion-set threatActor # # Filter out ATT&CK groups (intrusion-set) from bundle for group in attack.query([Filter("type", "=", "intrusion-set")]): if getattr(group, "revoked", None): # Object is revoked, add to notification list but do not add to facts that should be added to the platform notify.append(group) continue if getattr(group, "x_mitre_deprecated", None): # Object is revoked, add to notification list AND continue to add to facts that should be added to the platform notify.append(group) for alias in getattr(group, "aliases", []): if group.name != alias: handle_fact(client.fact("alias").bidirectional( "threatActor", group.name, "threatActor", alias), output_format=output_format) # ATT&CK concept STIX Properties # ========================================================================== # Software relationship where relationship_type == "uses", # points to a target object with type== "malware" or "tool" for tool in attack.related_to(group, relationship_type="uses"): if tool.type not in ("malware", "tool"): continue chain = act.api.fact.fact_chain( client.fact("classifiedAs").source("content", "*").destination( "tool", tool.name.lower()), client.fact("observedIn").source("content", "*").destination( "event", "*"), client.fact("attributedTo").source("event", "*").destination( "incident", "*"), client.fact("attributedTo").source( "incident", "*").destination("threatActor", group.name)) for fact in chain: handle_fact(fact, output_format=output_format) # ATT&CK concept STIX Properties # ========================================================================== # Technqiues relationship where relationship_type == "uses", points to # a target object with type == "attack-pattern" for technique in attack.related_to(group, relationship_type="uses"): if technique.type != "attack-pattern": continue chain = act.api.fact.fact_chain( client.fact("classifiedAs").source("event", "*").destination( "technique", technique.name), client.fact("attributedTo").source("event", "*").destination( "incident", "*"), client.fact("attributedTo").source( "incident", "*").destination("threatActor", group.name)) for fact in chain: handle_fact(fact, output_format=output_format) return notify
class MitreExtractor: """ This class extract Mitre techniques and sub techniques that are represented as "attack-pattern" in STIX format. The STIX data is collected in JSON format by requesting the specified URL. url: must point to json stix location kill_chain_name: mitre-attack, mitre-mbc... """ url = "" kill_chain_name = "" def __init__(self): """Download and store in memory the STIX data on instantiation.""" if self.kill_chain_name == "": raise ValueError( f"Kill chain name not specified in class {self.__class__.__name__}" ) if self.url == "": raise ValueError( f"URL not specified in class {self.__class__.__name__}") logging.info(f"Downloading STIX data at: {self.url}") stix_json = requests.get(self.url).json() self._memory_store = MemoryStore(stix_data=stix_json["objects"]) @staticmethod def _remove_deprecated_objetcs(stix_objects) -> List[AttackPattern]: """Remove any revoked or deprecated objects from queries made to the data source.""" return list( filter( lambda x: x.get("x_mitre_deprecated", False) is False and x. get("revoked", False) is False, stix_objects, )) def _get_tactics(self) -> List[Dict]: """Get tactics IDs from Mitre matrix.""" # Only one matrix for enterprise att&ck framework matrix = self._remove_deprecated_objetcs( self._memory_store.query([ Filter("type", "=", "x-mitre-matrix"), ]))[0] return list(map(self._memory_store.get, matrix["tactic_refs"])) def _get_techniques_from_tactic(self, tactic: str) -> List[AttackPattern]: """Get techniques and sub techniques from a Mitre tactic (kill_chain_phases->phase_name)""" techniques = self._remove_deprecated_objetcs( self._memory_store.query([ Filter("type", "=", "attack-pattern"), Filter("kill_chain_phases.phase_name", "=", tactic), Filter("kill_chain_phases.kill_chain_name", "=", self.kill_chain_name), ])) return techniques def _get_parent_technique_from_subtechnique( self, technique: AttackPattern) -> AttackPattern: """Get parent technique of a sub technique using the technique ID TXXXX.YYY""" sub_id = technique["external_references"][0]["external_id"].split( ".")[0] parent_technique = self._remove_deprecated_objetcs( self._memory_store.query([ Filter("type", "=", "attack-pattern"), Filter("external_references.external_id", "=", sub_id), ]))[0] return parent_technique def run(self) -> Dict[str, Dict[str, str]]: """Iterate over every technique over every tactic. If the technique is a sub technique, then we also search for the parent technique name. """ logging.info("Starting extraction...") data: Dict[str, Dict[str, str]] = {} for tactic in self._get_tactics(): data[tactic["name"]] = {} for technique in self._get_techniques_from_tactic( tactic["x_mitre_shortname"]): tid = technique["external_references"][0]["external_id"] technique_name = technique["name"].split("::")[0] if technique["x_mitre_is_subtechnique"]: parent_technique = self._get_parent_technique_from_subtechnique( technique) data[tactic["name"]][ tid] = f"{parent_technique['name']}::{technique_name}" else: data[tactic["name"]][tid] = technique_name return data