# This file is Copyright 2019 Volatility Foundation and licensed under the Volatility Software License 1.0
# which is available at https://www.volatilityfoundation.org/license/vsl-v1.0
#
from typing import List, Tuple, Optional
import logging
from volatility3.framework import interfaces
from volatility3.framework import renderers, symbols
from volatility3.framework.configuration import requirements
from volatility3.framework.objects import utility
from volatility3.framework.renderers import format_hints
from volatility3.plugins.linux import pslist
vollog = logging.getLogger(__name__)
[docs]
class Malfind(interfaces.plugins.PluginInterface):
"""Lists process memory ranges that potentially contain injected code."""
_required_framework_version = (2, 0, 0)
_version = (1, 0, 4)
[docs]
@classmethod
def get_requirements(cls) -> List[interfaces.configuration.RequirementInterface]:
return [
requirements.ModuleRequirement(
name="kernel",
description="Linux kernel",
architectures=["Intel32", "Intel64"],
),
requirements.VersionRequirement(
name="pslist", component=pslist.PsList, version=(4, 0, 0)
),
requirements.ListRequirement(
name="pid",
description="Filter on specific process IDs",
element_type=int,
optional=True,
),
requirements.IntRequirement(
name="dump-size",
description="Amount of bytes to dump for each dirty region/page found - Default 64 bytes",
optional=True,
default=64,
),
requirements.BooleanRequirement(
name="dump-page",
description="Dump each dirty page and content - Default off",
optional=True,
default=False,
),
]
def _list_injections(
self, task
) -> Tuple[interfaces.objects.ObjectInterface, Optional[str], bytes]:
"""Generate memory regions for a process that may contain injected
code."""
proc_layer_name = task.add_process_layer()
if not proc_layer_name:
return None
proc_layer = self.context.layers[proc_layer_name]
dump_size = self.config["dump-size"]
# Dumping page defaults to off, as in case a whole r-xp region is dirty
# this would likely dump 1000's of pages which might not always be wise nor necessary
dump_page = self.config["dump-page"]
for vma in task.mm.get_vma_iter():
vma_name = vma.get_name(self.context, task)
vollog.debug(
f"Injections : processing PID {task.pid} : VMA {vma_name} : {hex(vma.vm_start)}-{hex(vma.vm_end)}"
)
# If is_suspicious returns true, this means at least one page
# in the region is dirty. If dump_page is true, then we dump
# all dirty pages
if vma.is_suspicious(proc_layer) and vma_name != "[vdso]":
malicious_pages = vma.get_malicious_pages(proc_layer)
offset = 0
if dump_page:
# Dumping each dirty page
for page_addr in malicious_pages:
offset = page_addr - vma.vm_start
data = proc_layer.read(page_addr, dump_size, pad=True)
yield (
vma,
f"{vma_name}, page address: {page_addr:#x}, offset: {offset:#x}",
data,
offset,
)
else:
# Original behaviour - Dump the start of the region (not necessarily matching the dirty page)
data = proc_layer.read(vma.vm_start, dump_size, pad=True)
yield vma, vma_name, data, offset
def _generator(self, tasks):
# determine if we're on a 32 or 64 bit kernel
vmlinux = self.context.modules[self.config["kernel"]]
is_32bit_arch = not symbols.symbol_table_is_64bit(
context=self.context, symbol_table_name=vmlinux.symbol_table_name
)
for task in tasks:
process_name = utility.array_to_string(task.comm)
for vma, vma_name, data, offset in self._list_injections(task):
if is_32bit_arch:
architecture = "intel"
else:
architecture = "intel64"
disasm = renderers.Disassembly(
data, vma.vm_start + offset, architecture
)
yield (
0,
(
task.pid,
process_name,
format_hints.Hex(vma.vm_start),
format_hints.Hex(vma.vm_end),
vma_name or renderers.NotAvailableValue(),
vma.get_protection(),
format_hints.HexBytes(data),
disasm,
),
)
[docs]
def run(self):
filter_func = pslist.PsList.create_pid_filter(self.config.get("pid", None))
return renderers.TreeGrid(
[
("PID", int),
("Process", str),
("Start", format_hints.Hex),
("End", format_hints.Hex),
("Path", str),
("Protection", str),
("Hexdump", format_hints.HexBytes),
("Disasm", renderers.Disassembly),
],
self._generator(
pslist.PsList.list_tasks(
self.context, self.config["kernel"], filter_func=filter_func
)
),
)