diff --git a/volatility3/framework/plugins/windows/suspended_threads.py b/volatility3/framework/plugins/windows/suspended_threads.py new file mode 100644 index 000000000..2cc0673d7 --- /dev/null +++ b/volatility3/framework/plugins/windows/suspended_threads.py @@ -0,0 +1,147 @@ +import logging + +from typing import Dict +from functools import partial + +from volatility3.framework import renderers, interfaces, exceptions +from volatility3.framework.configuration import requirements +from volatility3.framework.renderers import format_hints +import volatility3.plugins.windows.pslist as pslist +import volatility3.plugins.windows.threads as threads +import volatility3.plugins.windows.pe_symbols as pe_symbols + +from volatility3.framework.objects import utility + +vollog = logging.getLogger(__name__) + + +class SuspendedThreads(interfaces.plugins.PluginInterface): + """Enumerates suspended threads.""" + + _required_framework_version = (2, 13, 0) + _version = (1, 0, 0) + + @classmethod + def get_requirements(cls): + return [ + requirements.ModuleRequirement( + name="kernel", + description="Windows kernel", + architectures=["Intel32", "Intel64"], + ), + requirements.VersionRequirement( + name="pslist", component=pslist.PsList, version=(2, 0, 0) + ), + requirements.VersionRequirement( + name="pe_symbols", component=pe_symbols.PESymbols, version=(1, 0, 0) + ), + requirements.VersionRequirement( + name="threads", component=threads.Threads, version=(1, 0, 0) + ), + ] + + def _generator(self): + """ + The goal of this plugin is to report on threads that are suspended + + Legitimate programs can start threads suspended but then will later resume them + + Subsets of malware techniques, such as EDR evasion and process hollowing, + create suspended threads and do not resume them. These are the threads that this + plugin is designed to catch. + + See the whitepaper from our DEF CON 2024 presentation for more details: + + https://www.volexity.com/wp-content/uploads/2024/08/Defcon24_EDR_Evasion_Detection_White-Paper_Andrew-Case.pdf + """ + kernel = self.context.modules[self.config["kernel"]] + + vads_cache: Dict[int, pe_symbols.PESymbols.ranges_type] = {} + + proc_modules = None + + # walk the threads of each process checking for suspended threads + for proc in pslist.PsList.list_processes( + context=self.context, + layer_name=kernel.layer_name, + symbol_table=kernel.symbol_table_name, + ): + for thread in threads.Threads.list_threads(kernel, proc): + try: + # we only care if the thread is suspended + if thread.Tcb.SuspendCount == 0: + continue + + # 4 == terminated + if thread.Tcb.State == 4: + continue + + owner_proc = thread.owning_process() + owner_proc_pid = thread.Cid.UniqueProcess + owner_proc_name = utility.array_to_string(owner_proc.ImageFileName) + thread_tid = thread.Cid.UniqueThread + thread_start_addr = thread.StartAddress + thread_win32_addr = thread.Win32StartAddress + except exceptions.InvalidAddressException: + continue + + # Nothing useful to report if a process doesn't have VADs.. Also a sign of smear/terminated + vads = pe_symbols.PESymbols.get_vads_for_process_cache(vads_cache, owner_proc) + if not vads: + continue + + # Only compute this if needed as its expensive and 99.9% of samples + # will not have suspended threads + if not proc_modules: + proc_modules = pe_symbols.PESymbols.get_process_modules( + self.context, kernel.layer_name, kernel.symbol_table_name, None + ) + + path_and_symbol = partial( + pe_symbols.PESymbols.path_and_symbol_for_address, + self.context, + self.config_path, + proc_modules, + ) + + start_file, start_sym = path_and_symbol(vads, thread_start_addr) + win32_file, win32_sym = path_and_symbol(vads, thread_win32_addr) + + # the only false positive found in mass scanning of samples + if start_file and start_file.endswith("\\WorkFoldersShell.dll"): + continue + + if win32_file and win32_file.endswith("\\WorkFoldersShell.dll"): + continue + + yield ( + 0, + ( + owner_proc_name, + owner_proc_pid, + thread_tid, + start_file or renderers.NotAvailableValue(), + start_sym or renderers.NotAvailableValue(), + format_hints.Hex(thread_start_addr), + win32_file or renderers.NotAvailableValue(), + win32_sym or renderers.NotAvailableValue(), + format_hints.Hex(thread_win32_addr), + ), + ) + + def run(self): + return renderers.TreeGrid( + [ + ("Process", str), + ("PID", int), + ("TID", int), + ("StartFile", str), + ("StartSymbol", str), + ("StartAddress", format_hints.Hex), + ("Win32StartFile", str), + ("Win32StartSymbol", str), + ("Win32StartAddress", format_hints.Hex), + ], + self._generator(), + ) +