Merge pull request #1167 from volatilityfoundation/process_ghosting

Add processghosting plugin to detect process ghosting and related tec…

volatility3/framework/plugins/windows/processghosting.py

@@ -0,0 +1,104 @@
+# This file is Copyright 2024 Volatility Foundation and licensed under the Volatility Software License 1.0
+# which is available at https://www.volatilityfoundation.org/license/vsl-v1.0
+#
+import logging
+import contextlib
+
+from volatility3.framework import interfaces, exceptions
+from volatility3.framework import renderers
+from volatility3.framework.configuration import requirements
+from volatility3.framework.objects import utility
+from volatility3.framework.renderers import format_hints
+from volatility3.plugins.windows import pslist
+
+vollog = logging.getLogger(__name__)
+
+
+class ProcessGhosting(interfaces.plugins.PluginInterface):
+    """Lists processes whose DeletePending bit is set or whose FILE_OBJECT is set to 0"""
+
+    _required_framework_version = (2, 4, 0)
+
+    @classmethod
+    def get_requirements(cls):
+        # Since we're calling the plugin, make sure we have the plugin's requirements
+        return [
+            requirements.ModuleRequirement(
+                name="kernel",
+                description="Windows kernel",
+                architectures=["Intel32", "Intel64"],
+            ),
+            requirements.VersionRequirement(
+                name="pslist", component=pslist.PsList, version=(2, 0, 0)
+            ),
+        ]
+
+    def _generator(self, procs):
+        kernel = self.context.modules[self.config["kernel"]]
+
+        if not kernel.get_type("_EPROCESS").has_member("ImageFilePointer"):
+            vollog.warning(
+                "This plugin only supports Windows 10 builds when the ImageFilePointer member of _EPROCESS is present"
+            )
+            return
+
+        for proc in procs:
+            delete_pending = renderers.UnreadableValue()
+            process_name = utility.array_to_string(proc.ImageFileName)
+
+            # if it is 0 then its a side effect of process ghosting
+            if proc.ImageFilePointer.vol.offset != 0:
+                try:
+                    file_object = proc.ImageFilePointer
+                    delete_pending = file_object.DeletePending
+                except exceptions.InvalidAddressException:
+                    file_object = 0
+
+            # ImageFilePointer equal to 0 means process ghosting or similar techniques were used
+            else:
+                file_object = 0
+
+            if isinstance(delete_pending, int) and delete_pending not in [0, 1]:
+                vollog.debug(
+                    f"Invalid delete_pending value {delete_pending} found for {process_name} {proc.UniqueProcessId}"
+                )
+
+            # delete_pending besides 0 or 1 = smear
+            if file_object == 0 or delete_pending == 1:
+                path = renderers.UnreadableValue()
+                if file_object:
+                    with contextlib.suppress(exceptions.InvalidAddressException):
+                        path = file_object.FileName.String
+
+                yield (
+                    0,
+                    (
+                        proc.UniqueProcessId,
+                        process_name,
+                        format_hints.Hex(file_object),
+                        delete_pending,
+                        path,
+                    ),
+                )
+
+    def run(self):
+        filter_func = pslist.PsList.create_active_process_filter()
+        kernel = self.context.modules[self.config["kernel"]]
+
+        return renderers.TreeGrid(
+            [
+                ("PID", int),
+                ("Process", str),
+                ("FILE_OBJECT", format_hints.Hex),
+                ("DeletePending", str),
+                ("Path", str),
+            ],
+            self._generator(
+                pslist.PsList.list_processes(
+                    context=self.context,
+                    layer_name=kernel.layer_name,
+                    symbol_table=kernel.symbol_table_name,
+                    filter_func=filter_func,
+                )
+            ),
+        )

volatility3/framework/plugins/windows/pslist.py

@@ -136,6 +136,29 @@ class PsList(interfaces.plugins.PluginInterface, timeliner.TimeLinerInterface):
                 filter_func = lambda x: x.UniqueProcessId not in filter_list
         return filter_func
 
+    @classmethod
+    def create_active_process_filter(
+        cls,
+    ) -> Callable[[interfaces.objects.ObjectInterface], bool]:
+        """A factory for producing a filter function that only returns
+           active, userland processes. This prevents plugins from operating on terminated
+           processes that are still in the process list due to smear or handle leaks as well
+           as kernel processes (System, Registry, etc.). Use of this filter for plugins searching
+           for system state anomalies significantly reduces false positive in smeared and terminated
+           processes.
+        Returns:
+            Filter function for passing to the `list_processes` method
+        """
+
+        return lambda x: not (
+            x.is_valid()
+            and x.ActiveThreads > 0
+            and x.UniqueProcessId != 4
+            and x.InheritedFromUniqueProcessId != 4
+            and x.ExitTime.QuadPart == 0
+            and x.get_handle_count() != renderers.UnreadableValue()
+        )
+
     @classmethod
     def create_name_filter(
         cls, name_list: List[str] = None, exclude: bool = False