driver-analysis

name: Driver Analysis description: Windows kernel driver analysis — DriverEntry, dispatch table, IOCTL handlers, vulnerability audit tags: [driver, kernel, windows, ioctl, vulnerability]

Task: Windows Kernel Driver Analysis. You are analyzing a kernel-mode driver binary.

Mandatory First Steps

1. Find DriverEntry — usually the binary entry point
   • Signature: NTSTATUS DriverEntry(DRIVER_OBJECT*, UNICODE_STRING*)
   • Use decompile_function on the entry point
2. From DriverEntry, extract:
   • MajorFunction dispatch table assignments
   • DriverUnload pointer
   • DeviceName and SymbolicLinkName
3. Identify IOCTL handlers — look for IRP_MJ_DEVICE_CONTROL dispatch entry

Key Data Structures

Use create_struct and set_type early — these appear in virtually every driver:

• DRIVER_OBJECT, DEVICE_OBJECT
• IRP, IO_STACK_LOCATION
• UNICODE_STRING

Apply types with set_function_prototype and apply_type_to_variable to make decompiled code readable immediately.

IOCTL Analysis

For each IRP_MJ_DEVICE_CONTROL handler:

1. decompile_function on the dispatch function
2. Find the switch statement on IoControlCode
3. For each IOCTL code, document:
   • IOCTL value and decoded method/access
   • Expected input/output buffer sizes
   • Operation performed
4. Check for dangerous patterns:
   • Kernel memory read/write gadgets
   • Process token manipulation
   • Arbitrary code execution paths

Common Vulnerabilities to Flag

• KeSetEvent with user-controlled address — kernel write primitive
• Missing ProbeForRead/ProbeForWrite before kernel-mode buffer copy
• Unchecked buffer sizes in METHOD_NEITHER IOCTLs — pool overflow
• MmMapIoSpace with user-supplied physical address — arbitrary physical memory access
• Direct stack buffer reads without size validation — kernel stack overflow
• ObReferenceObjectByHandle without proper access checks

Analysis Workflow

1. Map the dispatch table → understand all supported IRPs
2. Deep-dive each IOCTL handler → document input/output
3. Trace data flow from usermode input to kernel operations
4. Flag every path where user-controlled data reaches a sensitive kernel API
5. Rename functions as you understand them: DispatchDeviceControl, HandleIoctlReadPhysMem, etc.