-
Notifications
You must be signed in to change notification settings - Fork 561
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Merge branch 'master' into feat/1755
- Loading branch information
Showing
46 changed files
with
2,323 additions
and
855 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,161 @@ | ||
# Copyright (C) 2024 Mandiant, Inc. All Rights Reserved. | ||
# Licensed under the Apache License, Version 2.0 (the "License"); | ||
# you may not use this file except in compliance with the License. | ||
# You may obtain a copy of the License at: [package root]/LICENSE.txt | ||
# Unless required by applicable law or agreed to in writing, software distributed under the License | ||
# is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | ||
# See the License for the specific language governing permissions and limitations under the License. | ||
import logging | ||
from typing import Dict, List, Tuple, Optional | ||
from pathlib import Path | ||
from zipfile import ZipFile | ||
from collections import defaultdict | ||
|
||
from capa.exceptions import UnsupportedFormatError | ||
from capa.features.extractors.vmray.models import File, Flog, SummaryV2, StaticData, FunctionCall, xml_to_dict | ||
|
||
logger = logging.getLogger(__name__) | ||
|
||
DEFAULT_ARCHIVE_PASSWORD = b"infected" | ||
|
||
SUPPORTED_FLOG_VERSIONS = ("2",) | ||
|
||
|
||
class VMRayAnalysis: | ||
def __init__(self, zipfile_path: Path): | ||
self.zipfile = ZipFile(zipfile_path, "r") | ||
|
||
# summary_v2.json is the entry point to the entire VMRay archive and | ||
# we use its data to find everything else that we need for capa | ||
self.sv2 = SummaryV2.model_validate_json( | ||
self.zipfile.read("logs/summary_v2.json", pwd=DEFAULT_ARCHIVE_PASSWORD) | ||
) | ||
self.file_type: str = self.sv2.analysis_metadata.sample_type | ||
|
||
# flog.xml contains all of the call information that VMRay captured during execution | ||
flog_xml = self.zipfile.read("logs/flog.xml", pwd=DEFAULT_ARCHIVE_PASSWORD) | ||
flog_dict = xml_to_dict(flog_xml) | ||
self.flog = Flog.model_validate(flog_dict) | ||
|
||
if self.flog.analysis.log_version not in SUPPORTED_FLOG_VERSIONS: | ||
raise UnsupportedFormatError( | ||
"VMRay feature extractor does not support flog version %s" % self.flog.analysis.log_version | ||
) | ||
|
||
self.exports: Dict[int, str] = {} | ||
self.imports: Dict[int, Tuple[str, str]] = {} | ||
self.sections: Dict[int, str] = {} | ||
self.process_ids: Dict[int, int] = {} | ||
self.process_threads: Dict[int, List[int]] = defaultdict(list) | ||
self.process_calls: Dict[int, Dict[int, List[FunctionCall]]] = defaultdict(lambda: defaultdict(list)) | ||
self.base_address: int | ||
|
||
self.sample_file_name: Optional[str] = None | ||
self.sample_file_analysis: Optional[File] = None | ||
self.sample_file_static_data: Optional[StaticData] = None | ||
|
||
self._find_sample_file() | ||
|
||
# VMRay analysis archives in various shapes and sizes and file type does not definitively tell us what data | ||
# we can expect to find in the archive, so to be explicit we check for the various pieces that we need at | ||
# minimum to run capa analysis | ||
if self.sample_file_name is None or self.sample_file_analysis is None: | ||
raise UnsupportedFormatError("VMRay archive does not contain sample file (file_type: %s)" % self.file_type) | ||
|
||
if not self.sample_file_static_data: | ||
raise UnsupportedFormatError("VMRay archive does not contain static data (file_type: %s)" % self.file_type) | ||
|
||
if not self.sample_file_static_data.pe and not self.sample_file_static_data.elf: | ||
raise UnsupportedFormatError( | ||
"VMRay feature extractor only supports PE and ELF at this time (file_type: %s)" % self.file_type | ||
) | ||
|
||
# VMRay does not store static strings for the sample file so we must use the source file | ||
# stored in the archive | ||
sample_sha256: str = self.sample_file_analysis.hash_values.sha256.lower() | ||
sample_file_path: str = f"internal/static_analyses/{sample_sha256}/objects/files/{sample_sha256}" | ||
|
||
logger.debug("file_type: %s, file_path: %s", self.file_type, sample_file_path) | ||
|
||
self.sample_file_buf: bytes = self.zipfile.read(sample_file_path, pwd=DEFAULT_ARCHIVE_PASSWORD) | ||
|
||
self._compute_base_address() | ||
self._compute_imports() | ||
self._compute_exports() | ||
self._compute_sections() | ||
self._compute_process_ids() | ||
self._compute_process_threads() | ||
self._compute_process_calls() | ||
|
||
def _find_sample_file(self): | ||
for file_name, file_analysis in self.sv2.files.items(): | ||
if file_analysis.is_sample: | ||
# target the sample submitted for analysis | ||
self.sample_file_name = file_name | ||
self.sample_file_analysis = file_analysis | ||
|
||
if file_analysis.ref_static_data: | ||
# like "path": ["static_data","static_data_0"] where "static_data_0" is the summary_v2 static data | ||
# key for the file's static data | ||
self.sample_file_static_data = self.sv2.static_data[file_analysis.ref_static_data.path[1]] | ||
|
||
break | ||
|
||
def _compute_base_address(self): | ||
assert self.sample_file_static_data is not None | ||
if self.sample_file_static_data.pe: | ||
self.base_address = self.sample_file_static_data.pe.basic_info.image_base | ||
|
||
def _compute_exports(self): | ||
assert self.sample_file_static_data is not None | ||
if self.sample_file_static_data.pe: | ||
for export in self.sample_file_static_data.pe.exports: | ||
self.exports[export.address] = export.api.name | ||
|
||
def _compute_imports(self): | ||
assert self.sample_file_static_data is not None | ||
if self.sample_file_static_data.pe: | ||
for module in self.sample_file_static_data.pe.imports: | ||
for api in module.apis: | ||
self.imports[api.address] = (module.dll, api.api.name) | ||
|
||
def _compute_sections(self): | ||
assert self.sample_file_static_data is not None | ||
if self.sample_file_static_data.pe: | ||
for pefile_section in self.sample_file_static_data.pe.sections: | ||
self.sections[pefile_section.virtual_address] = pefile_section.name | ||
elif self.sample_file_static_data.elf: | ||
for elffile_section in self.sample_file_static_data.elf.sections: | ||
self.sections[elffile_section.header.sh_addr] = elffile_section.header.sh_name | ||
|
||
def _compute_process_ids(self): | ||
for process in self.sv2.processes.values(): | ||
# we expect VMRay's monitor IDs to be unique, but OS PIDs may be reused | ||
assert process.monitor_id not in self.process_ids.keys() | ||
self.process_ids[process.monitor_id] = process.os_pid | ||
|
||
def _compute_process_threads(self): | ||
# logs/flog.xml appears to be the only file that contains thread-related data | ||
# so we use it here to map processes to threads | ||
for function_call in self.flog.analysis.function_calls: | ||
pid: int = self.get_process_os_pid(function_call.process_id) # flog.xml uses process monitor ID, not OS PID | ||
tid: int = function_call.thread_id | ||
|
||
assert isinstance(pid, int) | ||
assert isinstance(tid, int) | ||
|
||
if tid not in self.process_threads[pid]: | ||
self.process_threads[pid].append(tid) | ||
|
||
def _compute_process_calls(self): | ||
for function_call in self.flog.analysis.function_calls: | ||
pid: int = self.get_process_os_pid(function_call.process_id) # flog.xml uses process monitor ID, not OS PID | ||
tid: int = function_call.thread_id | ||
|
||
assert isinstance(pid, int) | ||
assert isinstance(tid, int) | ||
|
||
self.process_calls[pid][tid].append(function_call) | ||
|
||
def get_process_os_pid(self, monitor_id: int) -> int: | ||
return self.process_ids[monitor_id] |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,53 @@ | ||
# Copyright (C) 2024 Mandiant, Inc. All Rights Reserved. | ||
# Licensed under the Apache License, Version 2.0 (the "License"); | ||
# you may not use this file except in compliance with the License. | ||
# You may obtain a copy of the License at: [package root]/LICENSE.txt | ||
# Unless required by applicable law or agreed to in writing, software distributed under the License | ||
# is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | ||
# See the License for the specific language governing permissions and limitations under the License. | ||
import logging | ||
from typing import Tuple, Iterator | ||
|
||
from capa.features.insn import API, Number | ||
from capa.features.common import String, Feature | ||
from capa.features.address import Address | ||
from capa.features.extractors.vmray.models import PARAM_TYPE_INT, PARAM_TYPE_STR, Param, FunctionCall, hexint | ||
from capa.features.extractors.base_extractor import CallHandle, ThreadHandle, ProcessHandle | ||
|
||
logger = logging.getLogger(__name__) | ||
|
||
|
||
def get_call_param_features(param: Param, ch: CallHandle) -> Iterator[Tuple[Feature, Address]]: | ||
if param.deref is not None: | ||
# pointer types contain a special "deref" member that stores the deref'd value | ||
# so we check for this first and ignore Param.value as this always contains the | ||
# deref'd pointer value | ||
if param.deref.value is not None: | ||
if param.deref.type_ in PARAM_TYPE_INT: | ||
yield Number(hexint(param.deref.value)), ch.address | ||
elif param.deref.type_ in PARAM_TYPE_STR: | ||
yield String(param.deref.value), ch.address | ||
else: | ||
logger.debug("skipping deref param type %s", param.deref.type_) | ||
elif param.value is not None: | ||
if param.type_ in PARAM_TYPE_INT: | ||
yield Number(hexint(param.value)), ch.address | ||
|
||
|
||
def extract_call_features(ph: ProcessHandle, th: ThreadHandle, ch: CallHandle) -> Iterator[Tuple[Feature, Address]]: | ||
call: FunctionCall = ch.inner | ||
|
||
if call.params_in: | ||
for param in call.params_in.params: | ||
yield from get_call_param_features(param, ch) | ||
|
||
yield API(call.name), ch.address | ||
|
||
|
||
def extract_features(ph: ProcessHandle, th: ThreadHandle, ch: CallHandle) -> Iterator[Tuple[Feature, Address]]: | ||
for handler in CALL_HANDLERS: | ||
for feature, addr in handler(ph, th, ch): | ||
yield feature, addr | ||
|
||
|
||
CALL_HANDLERS = (extract_call_features,) |
Oops, something went wrong.