def cape_name_from_yara(details, pid, results):
for hit in details.get("cape_yara", []) or []:
if File.yara_hit_provides_detection(hit):
if "detections2pid" not in results:
results.setdefault("detections2pid", {})
results["detections2pid"].setdefault(str(pid), [])
name = File.get_cape_name_from_yara_hit(hit)
if name not in results["detections2pid"][str(pid)]:
results["detections2pid"][str(pid)].append(name)
return name
def static_extraction(path):
try:
if not File.yara_initialized:
init_yara()
hits = File(path).get_yara(category="CAPE")
if not hits:
return False
# Get the file data
with open(path, "rb") as file_open:
file_data = file_open.read()
for hit in hits:
cape_name = File.get_cape_name_from_yara_hit(hit)
config = static_config_parsers(cape_name, path, file_data)
if config:
return config
return False
except Exception as e:
log.error(e)
return False
def process_file(self, file_path, append_file, metadata=None):
"""Process file.
@return: file_info
"""
if metadata is None:
metadata = {}
cape_name = ""
type_string = ""
if not os.path.exists(file_path):
return
file_info, pefile_object = File(file_path,
metadata.get("metadata",
"")).get_all()
cape_names = set()
if pefile_object:
self.results.setdefault("pefiles",
{}).setdefault(file_info["sha256"],
pefile_object)
if file_info.get("clamav") and processing_conf.detections.clamav:
clamav_detection = get_clamav_consensus(file_info["clamav"])
if clamav_detection:
add_family_detection(self.results, clamav_detection, "ClamAV",
file_info["sha256"])
# should we use dropped path here?
static_file_info(
file_info,
file_path,
str(self.task["id"]),
self.task.get("package", ""),
self.task.get("options", ""),
self.self_extracted,
self.results,
)
# Get the file data
with open(file_info["path"], "rb") as file_open:
file_data = file_open.read()
if metadata.get("pids", False):
file_info["pid"] = metadata["pids"][0] if len(
metadata["pids"]) == 1 else ",".join(metadata["pids"])
metastrings = metadata.get("metadata", "").split(";?")
if len(metastrings) > 2:
file_info["process_path"] = metastrings[1]
file_info["process_name"] = metastrings[1].rsplit("\\", 1)[-1]
if len(metastrings) > 3:
file_info["module_path"] = metastrings[2]
file_info["cape_type_code"] = 0
file_info["cape_type"] = ""
if metastrings and metastrings[0] and metastrings[0].isdigit():
file_info["cape_type_code"] = int(metastrings[0])
if file_info["cape_type_code"] == TYPE_STRING:
if len(metastrings) > 4:
type_string = metastrings[3]
elif file_info["cape_type_code"] == COMPRESSION:
file_info["cape_type"] = "Decompressed PE Image"
elif file_info["cape_type_code"] in inject_map:
file_info["cape_type"] = inject_map[
file_info["cape_type_code"]]
if len(metastrings) > 4:
file_info["target_path"] = metastrings[3]
file_info["target_process"] = metastrings[3].rsplit(
"\\", 1)[-1]
file_info["target_pid"] = metastrings[4]
elif file_info["cape_type_code"] in unpack_map:
file_info["cape_type"] = unpack_map[
file_info["cape_type_code"]]
if len(metastrings) > 4:
file_info["virtual_address"] = metastrings[3]
type_strings = file_info["type"].split()
if type_strings[0] in ("PE32+", "PE32"):
file_info["cape_type"] += pe_map[type_strings[0]]
if type_strings[2] == ("(DLL)"):
file_info["cape_type"] += "DLL"
else:
file_info["cape_type"] += "executable"
if file_info["cape_type_code"] in code_mapping:
file_info["cape_type"] = code_mapping[
file_info["cape_type_code"]]
type_strings = file_info["type"].split()
if type_strings[0] in ("PE32+", "PE32"):
file_info["cape_type"] += pe_map[type_strings[0]]
if type_strings[2] == ("(DLL)"):
file_info["cape_type"] += "DLL"
else:
file_info["cape_type"] += "executable"
if file_info["cape_type_code"] in name_mapping:
cape_name = name_mapping[file_info["cape_type_code"]]
append_file = True
# PlugX
elif file_info["cape_type_code"] == PLUGX_CONFIG:
file_info["cape_type"] = "PlugX Config"
if plugx_parser:
plugx_config = plugx_parser.parse_config(
file_data, len(file_data))
if plugx_config:
cape_name = "PlugX"
self.update_cape_configs(cape_name, plugx_config)
cape_names.add(cape_name)
else:
log.error(
"CAPE: PlugX config parsing failure - size many not be handled"
)
append_file = False
# Attempt to decrypt script dump
elif file_info["cape_type_code"] == SCRIPT_DUMP:
data = file_data.decode("utf-16").replace("\x00", "")
cape_name = "ScriptDump"
malwareconfig_loaded = False
try:
malwareconfig_parsers = os.path.join(
CUCKOO_ROOT, "modules", "processing", "parsers",
"CAPE")
file, pathname, description = imp.find_module(
cape_name, [malwareconfig_parsers])
module = imp.load_module(cape_name, file, pathname,
description)
malwareconfig_loaded = True
log.debug("CAPE: Imported parser %s", cape_name)
except ImportError:
log.debug("CAPE: parser: No module named %s", cape_name)
if malwareconfig_loaded:
try:
script_data = module.config(self, data)
if script_data and "more_eggs" in script_data["type"]:
bindata = script_data["data"]
sha256 = hashlib.sha256(bindata).hexdigest()
filepath = os.path.join(self.CAPE_path, sha256)
if "text" in script_data["datatype"]:
file_info["cape_type"] = "MoreEggsJS"
elif "binary" in script_data["datatype"]:
file_info["cape_type"] = "MoreEggsBin"
with open(filepath, "w") as cfile:
cfile.write(bindata)
self.script_dump_files.append(filepath)
else:
file_info["cape_type"] = "Script Dump"
log.info(
"CAPE: Script Dump does not contain known encrypted payload"
)
except Exception as e:
log.error(
"CAPE: malwareconfig parsing error with %s: %s",
cape_name, e)
append_file = True
# More_Eggs
elif file_info["cape_type_code"] == MOREEGGSJS_PAYLOAD:
file_info["cape_type"] = "More Eggs JS Payload"
cape_name = "MoreEggs"
append_file = True
# Process CAPE Yara hits
# Prefilter extracted data + beauty is better than oneliner:
all_files = []
for extracted_file in file_info.get("extracted_files", []):
yara_hits = extracted_file["cape_yara"]
if not yara_hits:
continue
if extracted_file.get("data", b""):
extracted_file_data = make_bytes(extracted_file["data"])
else:
with open(extracted_file["path"], "rb") as fil:
extracted_file_data = fil.read()
for yara in yara_hits:
all_files.append((
f"[{extracted_file.get('sha256', '')}]{file_info['path']}",
extracted_file_data,
yara,
))
for yara in file_info["cape_yara"]:
all_files.append((file_info["path"], file_data, yara))
executed_config_parsers = collections.defaultdict(set)
for tmp_path, tmp_data, hit in all_files:
# Check for a payload or config hit
try:
if File.yara_hit_provides_detection(hit):
file_info["cape_type"] = hit["meta"]["cape_type"]
cape_name = File.get_cape_name_from_yara_hit(hit)
cape_names.add(cape_name)
except Exception as e:
print(f"Cape type error: {e}")
type_strings = file_info["type"].split()
if "-bit" not in file_info["cape_type"]:
if type_strings[0] in ("PE32+", "PE32"):
file_info["cape_type"] += pe_map[type_strings[0]]
file_info["cape_type"] += "DLL" if type_strings[2] == (
"(DLL)") else "executable"
if cape_name and cape_name not in executed_config_parsers[tmp_path]:
tmp_config = static_config_parsers(cape_name, tmp_path,
tmp_data)
self.update_cape_configs(cape_name, tmp_config)
executed_config_parsers[tmp_path].add(cape_name)
if type_string:
log.info("CAPE: type_string: %s", type_string)
tmp_cape_name = File.get_cape_name_from_cape_type(type_string)
if tmp_cape_name and tmp_cape_name not in executed_config_parsers:
tmp_config = static_config_parsers(tmp_cape_name,
file_info["path"],
file_data)
if tmp_config:
cape_name = tmp_cape_name
cape_names.add(cape_name)
log.info("CAPE: config returned for: %s", cape_name)
self.update_cape_configs(cape_name, tmp_config)
self.add_family_detections(file_info, cape_names)
# Remove duplicate payloads from web ui
for cape_file in self.cape["payloads"] or []:
if file_info["size"] == cape_file["size"]:
if HAVE_PYDEEP:
ssdeep_grade = pydeep.compare(file_info["ssdeep"].encode(),
cape_file["ssdeep"].encode())
if ssdeep_grade >= ssdeep_threshold:
log.debug(
"CAPE duplicate output file skipped: ssdeep grade %d, threshold %d",
ssdeep_grade, ssdeep_threshold)
append_file = False
if file_info.get("entrypoint") and file_info.get(
"ep_bytes") and cape_file.get("entrypoint"):
if (file_info["entrypoint"] == cape_file["entrypoint"]
and file_info["cape_type_code"]
== cape_file["cape_type_code"] and
file_info["ep_bytes"] == cape_file["ep_bytes"]):
log.debug(
"CAPE duplicate output file skipped: matching entrypoint"
)
append_file = False
if append_file:
if HAVE_FLARE_CAPA:
pretime = timeit.default_timer()
capa_details = flare_capa_details(file_path, "cape")
if capa_details:
file_info["flare_capa"] = capa_details
self.add_statistic_tmp("flare_capa", "time", pretime=pretime)
self.cape["payloads"].append(file_info)
