reverse-skills-max: initial public release (restored, redacted, hardened)
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Copyright 2026 mukul975
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@@ -0,0 +1,361 @@
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---
|
||||
name: analyzing-bootkit-and-rootkit-samples
|
||||
description: 'Analyzes bootkit and advanced rootkit malware infecting the Master
|
||||
Boot Record (MBR), Volume Boot Record (VBR), or UEFI firmware for below-OS persistence,
|
||||
covering boot sector analysis, UEFI module inspection, and anti-rootkit detection.
|
||||
Use when compromise survives OS reinstallation or antivirus/EDR fails to detect
|
||||
malware despite clear infection signs.
|
||||
|
||||
'
|
||||
domain: cybersecurity
|
||||
subdomain: malware-analysis
|
||||
tags:
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||||
- malware
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||||
- bootkit
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||||
- rootkit
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||||
- UEFI
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||||
- MBR-analysis
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||||
version: 1.0.0
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author: mahipal
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||||
license: Apache-2.0
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||||
nist_csf:
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||||
- DE.AE-02
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||||
- RS.AN-03
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||||
- ID.RA-01
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||||
- DE.CM-01
|
||||
mitre_attack:
|
||||
- T1542.003
|
||||
- T1542.001
|
||||
- T1542.002
|
||||
- T1014
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||||
- T1547.006
|
||||
---
|
||||
|
||||
# Analyzing Bootkit and Rootkit Samples
|
||||
|
||||
## When to Use
|
||||
|
||||
- A system shows signs of compromise that persist through OS reinstallation
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||||
- Antivirus and EDR are unable to detect malware despite clear evidence of compromise
|
||||
- UEFI Secure Boot has been disabled or shows integrity violations
|
||||
- Memory forensics reveals rootkit behavior (hidden processes, hooked system calls)
|
||||
- Investigating nation-state level threats known to deploy bootkits (APT28, APT41, Equation Group)
|
||||
|
||||
**Do not use** for standard user-mode malware; bootkits and rootkits operate at a fundamentally different level requiring specialized analysis techniques.
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||||
|
||||
## Prerequisites
|
||||
|
||||
- Disk imaging tools (dd, FTK Imager) for acquiring MBR/VBR sectors
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||||
- UEFITool for UEFI firmware volume analysis and module extraction
|
||||
- chipsec for hardware-level firmware security assessment
|
||||
- Ghidra with x86 real-mode and 16-bit support for MBR code analysis
|
||||
- Volatility 3 for kernel-level rootkit artifact detection
|
||||
- Bootable Linux live USB for offline system analysis
|
||||
|
||||
## Workflow
|
||||
|
||||
### Step 1: Acquire Boot Sectors and Firmware
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||||
|
||||
Extract MBR, VBR, and UEFI firmware for offline analysis:
|
||||
|
||||
```bash
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||||
# Acquire MBR (first 512 bytes of disk)
|
||||
dd if=/dev/sda of=mbr.bin bs=512 count=1
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|
||||
# Acquire first track (usually contains bootkit code beyond MBR)
|
||||
dd if=/dev/sda of=first_track.bin bs=512 count=63
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|
||||
# Acquire VBR (Volume Boot Record - first sector of partition)
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||||
dd if=/dev/sda1 of=vbr.bin bs=512 count=1
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||||
|
||||
# Acquire UEFI System Partition
|
||||
mkdir /mnt/efi
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mount /dev/sda1 /mnt/efi
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||||
cp -r /mnt/efi/EFI /analysis/efi_backup/
|
||||
|
||||
# Dump UEFI firmware (requires chipsec or flashrom)
|
||||
# Using chipsec:
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||||
python chipsec_util.py spi dump firmware.rom
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|
||||
# Using flashrom:
|
||||
flashrom -p internal -r firmware.rom
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|
||||
# Verify firmware dump integrity
|
||||
sha256sum firmware.rom
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```
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|
||||
### Step 2: Analyze MBR/VBR for Bootkit Code
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|
||||
Examine boot sector code for malicious modifications:
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||||
|
||||
```bash
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# Disassemble MBR code (16-bit real mode)
|
||||
ndisasm -b16 mbr.bin > mbr_disasm.txt
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|
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# Compare MBR with known-good Windows MBR
|
||||
# Standard Windows MBR begins with: EB 5A 90 (JMP 0x5C, NOP)
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||||
# Standard Windows 10 MBR: 33 C0 8E D0 BC 00 7C (XOR AX,AX; MOV SS,AX; MOV SP,7C00h)
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||||
|
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python3 << 'PYEOF'
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with open("mbr.bin", "rb") as f:
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mbr = f.read()
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# Check MBR signature (bytes 510-511 should be 0x55AA)
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if mbr[510:512] == b'\x55\xAA':
|
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print("[*] Valid MBR signature (0x55AA)")
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else:
|
||||
print("[!] Invalid MBR signature")
|
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|
||||
# Check for known bootkit signatures
|
||||
bootkit_sigs = {
|
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b'\xE8\x00\x00\x5E\x81\xEE': "TDL4/Alureon bootkit",
|
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b'\xFA\x33\xC0\x8E\xD0\xBC\x00\x7C\x8B\xF4\x50\x07': "Standard Windows MBR (clean)",
|
||||
b'\xEB\x5A\x90\x4E\x54\x46\x53': "Standard NTFS VBR (clean)",
|
||||
}
|
||||
|
||||
for sig, name in bootkit_sigs.items():
|
||||
if sig in mbr:
|
||||
print(f"[{'!' if 'clean' not in name else '*'}] Signature match: {name}")
|
||||
|
||||
# Check partition table entries
|
||||
print("\nPartition Table:")
|
||||
for i in range(4):
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||||
offset = 446 + (i * 16)
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entry = mbr[offset:offset+16]
|
||||
if entry != b'\x00' * 16:
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boot_flag = "Active" if entry[0] == 0x80 else "Inactive"
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||||
part_type = entry[4]
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start_lba = int.from_bytes(entry[8:12], 'little')
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||||
size_lba = int.from_bytes(entry[12:16], 'little')
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print(f" Partition {i+1}: Type=0x{part_type:02X} {boot_flag} Start=LBA {start_lba} Size={size_lba} sectors")
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PYEOF
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||||
```
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||||
|
||||
### Step 3: Analyze UEFI Firmware for Implants
|
||||
|
||||
Inspect UEFI firmware volumes for unauthorized modules:
|
||||
|
||||
```bash
|
||||
# Extract UEFI firmware components with UEFITool
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||||
# GUI: Open firmware.rom -> Inspect firmware volumes
|
||||
# CLI:
|
||||
UEFIExtract firmware.rom all
|
||||
|
||||
# List all DXE drivers (most common target for UEFI implants)
|
||||
find firmware.rom.dump -name "*.efi" -exec file {} \;
|
||||
|
||||
# Compare against known-good firmware module list
|
||||
# Each UEFI module has a GUID - compare against vendor baseline
|
||||
|
||||
# Verify Secure Boot configuration
|
||||
python chipsec_main.py -m common.secureboot.variables
|
||||
|
||||
# Check SPI flash write protection
|
||||
python chipsec_main.py -m common.bios_wp
|
||||
|
||||
# Check for known UEFI malware patterns
|
||||
yara -r uefi_malware.yar firmware.rom
|
||||
```
|
||||
|
||||
```
|
||||
Known UEFI Bootkit Detection Points:
|
||||
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
|
||||
LoJax (APT28):
|
||||
- Modified SPI flash
|
||||
- Added DXE driver that drops agent to Windows
|
||||
- Persists through OS reinstall and disk replacement
|
||||
|
||||
BlackLotus:
|
||||
- Exploits CVE-2022-21894 to bypass Secure Boot
|
||||
- Modifies EFI System Partition bootloader
|
||||
- Installs kernel driver during boot
|
||||
|
||||
CosmicStrand:
|
||||
- Modifies CORE_DXE firmware module
|
||||
- Hooks kernel initialization during boot
|
||||
- Drops shellcode into Windows kernel memory
|
||||
|
||||
MoonBounce:
|
||||
- SPI flash implant in CORE_DXE module
|
||||
- Modified GetVariable() function
|
||||
- Deploys user-mode implant through boot chain
|
||||
|
||||
ESPecter:
|
||||
- Modifies Windows Boot Manager on ESP
|
||||
- Patches winload.efi to disable DSE
|
||||
- Loads unsigned kernel driver
|
||||
```
|
||||
|
||||
### Step 4: Detect Kernel-Level Rootkit Behavior
|
||||
|
||||
Analyze the running system for rootkit artifacts:
|
||||
|
||||
```bash
|
||||
# Memory forensics for rootkit detection
|
||||
# SSDT hook detection
|
||||
vol3 -f memory.dmp windows.ssdt | grep -v "ntoskrnl\|win32k"
|
||||
|
||||
# Hidden processes (DKOM)
|
||||
vol3 -f memory.dmp windows.psscan > psscan.txt
|
||||
vol3 -f memory.dmp windows.pslist > pslist.txt
|
||||
# Diff to find hidden processes
|
||||
|
||||
# Kernel callback registration (rootkits register callbacks for filtering)
|
||||
vol3 -f memory.dmp windows.callbacks
|
||||
|
||||
# Driver analysis
|
||||
vol3 -f memory.dmp windows.driverscan
|
||||
vol3 -f memory.dmp windows.modules
|
||||
|
||||
# Check for unsigned drivers
|
||||
vol3 -f memory.dmp windows.driverscan | while read line; do
|
||||
driver_path=$(echo "$line" | awk '{print $NF}')
|
||||
if [ -f "$driver_path" ]; then
|
||||
sigcheck -nobanner "$driver_path" 2>/dev/null | grep "Unsigned"
|
||||
fi
|
||||
done
|
||||
|
||||
# IDT hook detection
|
||||
vol3 -f memory.dmp windows.idt
|
||||
```
|
||||
|
||||
### Step 5: Boot Process Integrity Verification
|
||||
|
||||
Verify the integrity of the entire boot chain:
|
||||
|
||||
```bash
|
||||
# Verify Windows Boot Manager signature
|
||||
sigcheck -a C:\Windows\Boot\EFI\bootmgfw.efi
|
||||
|
||||
# Verify winload.efi
|
||||
sigcheck -a C:\Windows\System32\winload.efi
|
||||
|
||||
# Verify ntoskrnl.exe
|
||||
sigcheck -a C:\Windows\System32\ntoskrnl.exe
|
||||
|
||||
# Check Measured Boot logs (if TPM is available)
|
||||
# Windows: BCDEdit /enum firmware
|
||||
bcdedit /enum firmware
|
||||
|
||||
# Verify Secure Boot state
|
||||
Confirm-SecureBootUEFI # PowerShell cmdlet
|
||||
|
||||
# Check boot configuration for tampering
|
||||
bcdedit /v
|
||||
|
||||
# Look for boot configuration changes
|
||||
# testsigning: should be No
|
||||
# nointegritychecks: should be No
|
||||
# debug: should be No
|
||||
bcdedit | findstr /i "testsigning nointegritychecks debug"
|
||||
```
|
||||
|
||||
### Step 6: Document Bootkit/Rootkit Analysis
|
||||
|
||||
Compile comprehensive analysis findings:
|
||||
|
||||
```
|
||||
Analysis should document:
|
||||
- Boot sector (MBR/VBR) integrity status with hex comparison
|
||||
- UEFI firmware module inventory and integrity verification
|
||||
- Secure Boot status and any bypass mechanisms detected
|
||||
- Kernel-level hooks (SSDT, IDT, IRP, inline) identified
|
||||
- Hidden processes, drivers, and files discovered
|
||||
- Persistence mechanism (SPI flash, ESP, MBR, kernel driver)
|
||||
- Boot chain integrity verification results
|
||||
- Attribution to known bootkit families if possible
|
||||
- Remediation steps (reflash firmware, rebuild MBR, replace hardware)
|
||||
```
|
||||
|
||||
## Key Concepts
|
||||
|
||||
| Term | Definition |
|
||||
|------|------------|
|
||||
| **Bootkit** | Malware that infects the boot process (MBR, VBR, UEFI) to execute before the operating system loads, gaining persistent low-level control |
|
||||
| **MBR (Master Boot Record)** | First 512 bytes of a disk containing bootstrap code and partition table; MBR bootkits replace this code with malicious loaders |
|
||||
| **UEFI (Unified Extensible Firmware Interface)** | Modern firmware interface replacing BIOS; UEFI bootkits implant malicious modules in firmware volumes or modify the ESP |
|
||||
| **Secure Boot** | UEFI security feature verifying digital signatures of boot components; bootkits like BlackLotus exploit vulnerabilities to bypass it |
|
||||
| **SPI Flash** | Flash memory chip storing UEFI firmware; advanced bootkits like LoJax and MoonBounce modify SPI flash for firmware-level persistence |
|
||||
| **DKOM (Direct Kernel Object Manipulation)** | Rootkit technique modifying kernel structures to hide processes, files, and network connections without hooking functions |
|
||||
| **Driver Signature Enforcement (DSE)** | Windows security feature requiring kernel drivers to be digitally signed; bootkits disable DSE during boot to load unsigned rootkit drivers |
|
||||
|
||||
## Tools & Systems
|
||||
|
||||
- **UEFITool**: Open-source UEFI firmware image editor and parser for inspecting firmware volumes, drivers, and modules
|
||||
- **chipsec**: Intel hardware security assessment framework for verifying SPI flash protection, Secure Boot, and UEFI configuration
|
||||
- **Volatility**: Memory forensics framework with SSDT, IDT, callback, and driver analysis plugins for kernel rootkit detection
|
||||
- **GMER**: Windows rootkit detection tool scanning for SSDT hooks, IDT hooks, hidden processes, and modified kernel modules
|
||||
- **Bootkits Analyzer**: Specialized tool for analyzing MBR/VBR code including disassembly and comparison against known-good baselines
|
||||
|
||||
## Common Scenarios
|
||||
|
||||
### Scenario: Investigating Persistent Compromise Surviving OS Reinstallation
|
||||
|
||||
**Context**: An organization reimaged a compromised workstation, but the same C2 beaconing resumed within hours. Standard disk forensics finds no malware. UEFI bootkit is suspected.
|
||||
|
||||
**Approach**:
|
||||
1. Boot from a Linux live USB to avoid executing any compromised OS components
|
||||
2. Dump the SPI flash firmware using chipsec or flashrom for offline analysis
|
||||
3. Dump the MBR and VBR sectors with dd for boot sector analysis
|
||||
4. Copy the EFI System Partition for bootloader integrity verification
|
||||
5. Open the SPI dump in UEFITool and compare module GUIDs against vendor-provided firmware
|
||||
6. Look for additional or modified DXE drivers that should not be present
|
||||
7. Analyze any suspicious modules with Ghidra (x86_64 UEFI module format)
|
||||
8. Verify Secure Boot configuration and check for exploit-based bypasses
|
||||
|
||||
**Pitfalls**:
|
||||
- Analyzing the system while the compromised OS is running (rootkit may hide from live analysis)
|
||||
- Not checking SPI flash (only analyzing disk-based boot components misses firmware-level implants)
|
||||
- Assuming Secure Boot prevents all bootkits (known bypasses exist, e.g., CVE-2022-21894)
|
||||
- Not preserving the original firmware dump before reflashing (critical evidence for attribution)
|
||||
|
||||
## Output Format
|
||||
|
||||
```
|
||||
BOOTKIT / ROOTKIT ANALYSIS REPORT
|
||||
====================================
|
||||
System: Dell OptiPlex 7090 (UEFI, TPM 2.0)
|
||||
Firmware Version: 1.15.0 (Dell)
|
||||
Secure Boot: ENABLED (but bypassed)
|
||||
Capture Method: Linux Live USB + chipsec SPI dump
|
||||
|
||||
MBR/VBR ANALYSIS
|
||||
MBR Signature: Valid (0x55AA)
|
||||
MBR Code: MATCHES standard Windows 10 MBR (clean)
|
||||
VBR Code: MATCHES standard NTFS VBR (clean)
|
||||
|
||||
UEFI FIRMWARE ANALYSIS
|
||||
Total Modules: 287
|
||||
Vendor Expected: 285
|
||||
Extra Modules: 2 UNAUTHORIZED
|
||||
[!] DXE Driver GUID: {ABCD1234-...} "SmmAccessDxe_mod" (MODIFIED)
|
||||
Original Size: 12,288 bytes
|
||||
Current Size: 45,056 bytes (32KB ADDED)
|
||||
Entropy: 7.82 (HIGH - encrypted payload)
|
||||
|
||||
[!] DXE Driver GUID: {EFGH5678-...} "UefiPayloadDxe" (NEW - not in vendor firmware)
|
||||
Size: 28,672 bytes
|
||||
Function: Drops persistence agent during boot
|
||||
|
||||
BOOT CHAIN INTEGRITY
|
||||
bootmgfw.efi: MODIFIED (hash mismatch, Secure Boot bypass via CVE-2022-21894)
|
||||
winload.efi: MODIFIED (DSE disabled at load time)
|
||||
ntoskrnl.exe: CLEAN (but unsigned driver loaded after boot)
|
||||
|
||||
KERNEL ROOTKIT COMPONENTS
|
||||
Driver: C:\Windows\System32\drivers\null_mod.sys (unsigned, hidden)
|
||||
SSDT Hooks: 3 (NtQuerySystemInformation, NtQueryDirectoryFile, NtDeviceIoControlFile)
|
||||
Hidden Processes: 2 (PID 6784: beacon.exe, PID 6812: keylog.exe)
|
||||
Hidden Files: C:\Windows\System32\drivers\null_mod.sys
|
||||
|
||||
ATTRIBUTION
|
||||
Family: BlackLotus variant
|
||||
Confidence: HIGH (CVE-2022-21894 exploit, ESP modification pattern matches)
|
||||
|
||||
REMEDIATION
|
||||
1. Reflash SPI firmware with clean vendor image via hardware programmer
|
||||
2. Rebuild EFI System Partition from clean Windows installation media
|
||||
3. Reinstall OS from verified media
|
||||
4. Enable all firmware write protections
|
||||
5. Update firmware to latest version (patches CVE-2022-21894)
|
||||
```
|
||||
@@ -0,0 +1,97 @@
|
||||
# API Reference: Bootkit and Rootkit Analysis Tools
|
||||
|
||||
## dd - Boot Sector Extraction
|
||||
|
||||
### Syntax
|
||||
```bash
|
||||
dd if=/dev/sda of=mbr.bin bs=512 count=1 # MBR
|
||||
dd if=/dev/sda of=first_track.bin bs=512 count=63 # First track
|
||||
dd if=/dev/sda1 of=vbr.bin bs=512 count=1 # VBR
|
||||
```
|
||||
|
||||
## ndisasm - 16-bit Disassembly
|
||||
|
||||
### Syntax
|
||||
```bash
|
||||
ndisasm -b16 mbr.bin > mbr_disasm.txt
|
||||
ndisasm -b16 -o 0x7C00 mbr.bin # Set origin to MBR load address
|
||||
```
|
||||
|
||||
### Key Flags
|
||||
| Flag | Description |
|
||||
|------|-------------|
|
||||
| `-b16` | 16-bit real-mode disassembly |
|
||||
| `-b32` | 32-bit protected-mode |
|
||||
| `-o` | Origin address offset |
|
||||
|
||||
## UEFITool - Firmware Analysis
|
||||
|
||||
### CLI Syntax
|
||||
```bash
|
||||
UEFIExtract firmware.rom all # Extract all modules
|
||||
UEFIExtract firmware.rom <GUID> body # Extract specific module body
|
||||
```
|
||||
|
||||
### Output
|
||||
Extracts firmware volumes into a directory tree with each DXE driver, PEI module, and option ROM as separate files identified by GUID.
|
||||
|
||||
## chipsec - Hardware Security Assessment
|
||||
|
||||
### Syntax
|
||||
```bash
|
||||
python chipsec_main.py -m common.secureboot.variables # Check Secure Boot
|
||||
python chipsec_main.py -m common.bios_wp # SPI write protection
|
||||
python chipsec_main.py -m common.spi_lock # SPI lock status
|
||||
python chipsec_util.py spi dump firmware.rom # Dump SPI flash
|
||||
```
|
||||
|
||||
### Key Modules
|
||||
| Module | Purpose |
|
||||
|--------|---------|
|
||||
| `common.secureboot.variables` | Verify Secure Boot configuration |
|
||||
| `common.bios_wp` | Check BIOS write protection |
|
||||
| `common.spi_lock` | Verify SPI flash lock bits |
|
||||
| `common.smm` | SMM protection verification |
|
||||
|
||||
## Volatility 3 - Rootkit Detection Plugins
|
||||
|
||||
### Syntax
|
||||
```bash
|
||||
vol3 -f memory.dmp <plugin>
|
||||
```
|
||||
|
||||
### Rootkit Detection Plugins
|
||||
| Plugin | Purpose |
|
||||
|--------|---------|
|
||||
| `windows.ssdt` | System Service Descriptor Table hooks |
|
||||
| `windows.callbacks` | Kernel callback registrations |
|
||||
| `windows.driverscan` | Scan for driver objects |
|
||||
| `windows.modules` | List loaded kernel modules |
|
||||
| `windows.psscan` | Pool-tag scan for processes (finds hidden) |
|
||||
| `windows.pslist` | Active process list (DKOM-affected) |
|
||||
| `windows.idt` | Interrupt Descriptor Table hooks |
|
||||
|
||||
### Output Format
|
||||
```
|
||||
Offset Order Module Section Owner
|
||||
------- ----- ------ ------- -----
|
||||
0x... 0 ntoskrnl.exe .text ntoskrnl.exe
|
||||
0x... 73 UNKNOWN - rootkit.sys ← suspicious
|
||||
```
|
||||
|
||||
## flashrom - SPI Flash Dumping
|
||||
|
||||
### Syntax
|
||||
```bash
|
||||
flashrom -p internal -r firmware.rom # Read/dump
|
||||
flashrom -p internal -w clean.rom # Write/reflash
|
||||
flashrom -p internal --verify clean.rom # Verify flash contents
|
||||
```
|
||||
|
||||
## YARA - Firmware Pattern Scanning
|
||||
|
||||
### Syntax
|
||||
```bash
|
||||
yara -r uefi_malware.yar firmware.rom
|
||||
yara -s -r rules.yar firmware.rom # Show matching strings
|
||||
```
|
||||
@@ -0,0 +1,199 @@
|
||||
#!/usr/bin/env python3
|
||||
"""Bootkit and rootkit analysis agent for MBR/VBR/UEFI inspection and rootkit detection."""
|
||||
|
||||
import struct
|
||||
import hashlib
|
||||
import os
|
||||
import sys
|
||||
import subprocess
|
||||
import math
|
||||
from collections import Counter
|
||||
|
||||
|
||||
def read_mbr(disk_path_or_file):
|
||||
"""Read and parse the first 512 bytes (MBR) from a disk image or device."""
|
||||
with open(disk_path_or_file, "rb") as f:
|
||||
mbr = f.read(512)
|
||||
return mbr
|
||||
|
||||
|
||||
def validate_mbr_signature(mbr_data):
|
||||
"""Check the MBR boot signature at bytes 510-511 (should be 0x55AA)."""
|
||||
sig = mbr_data[510:512]
|
||||
valid = sig == b"\x55\xAA"
|
||||
return valid, sig.hex()
|
||||
|
||||
|
||||
def parse_partition_table(mbr_data):
|
||||
"""Parse the four 16-byte partition table entries starting at offset 446."""
|
||||
partitions = []
|
||||
for i in range(4):
|
||||
offset = 446 + (i * 16)
|
||||
entry = mbr_data[offset:offset + 16]
|
||||
if entry == b"\x00" * 16:
|
||||
continue
|
||||
boot_flag = entry[0]
|
||||
part_type = entry[4]
|
||||
start_lba = struct.unpack_from("<I", entry, 8)[0]
|
||||
size_lba = struct.unpack_from("<I", entry, 12)[0]
|
||||
partitions.append({
|
||||
"index": i + 1,
|
||||
"active": boot_flag == 0x80,
|
||||
"type_id": f"0x{part_type:02X}",
|
||||
"start_lba": start_lba,
|
||||
"size_sectors": size_lba,
|
||||
"size_mb": round(size_lba * 512 / (1024 * 1024), 1),
|
||||
})
|
||||
return partitions
|
||||
|
||||
|
||||
BOOTKIT_SIGNATURES = {
|
||||
b"\xE8\x00\x00\x5E\x81\xEE": "TDL4/Alureon bootkit",
|
||||
b"\xFA\x33\xC0\x8E\xD0\xBC\x00\x7C\x8B\xF4\x50\x07": "Standard Windows MBR (clean)",
|
||||
b"\xEB\x5A\x90\x4E\x54\x46\x53": "Standard NTFS VBR (clean)",
|
||||
b"\xEB\x52\x90\x4E\x54\x46\x53": "NTFS VBR variant (clean)",
|
||||
b"\x33\xC0\x8E\xD0\xBC\x00\x7C": "Windows 10 MBR (clean)",
|
||||
}
|
||||
|
||||
|
||||
def scan_bootkit_signatures(data):
|
||||
"""Scan boot sector data against known bootkit signatures."""
|
||||
matches = []
|
||||
for sig, name in BOOTKIT_SIGNATURES.items():
|
||||
if sig in data:
|
||||
offset = data.find(sig)
|
||||
matches.append({"signature": name, "offset": offset, "clean": "clean" in name})
|
||||
return matches
|
||||
|
||||
|
||||
def calculate_entropy(data):
|
||||
"""Calculate Shannon entropy of binary data."""
|
||||
if not data:
|
||||
return 0.0
|
||||
counter = Counter(data)
|
||||
length = len(data)
|
||||
entropy = -sum(
|
||||
(count / length) * math.log2(count / length)
|
||||
for count in counter.values()
|
||||
)
|
||||
return round(entropy, 4)
|
||||
|
||||
|
||||
def read_first_track(disk_path, num_sectors=63):
|
||||
"""Read the first track (typically 63 sectors) for extended bootkit code."""
|
||||
with open(disk_path, "rb") as f:
|
||||
data = f.read(num_sectors * 512)
|
||||
return data
|
||||
|
||||
|
||||
def analyze_boot_code(mbr_data):
|
||||
"""Analyze MBR bootstrap code (bytes 0-445) for suspicious patterns."""
|
||||
boot_code = mbr_data[:446]
|
||||
entropy = calculate_entropy(boot_code)
|
||||
sha256 = hashlib.sha256(boot_code).hexdigest()
|
||||
suspicious_patterns = []
|
||||
# Check for INT 13h hooking (common bootkit technique)
|
||||
if b"\xCD\x13" in boot_code:
|
||||
count = boot_code.count(b"\xCD\x13")
|
||||
suspicious_patterns.append(f"INT 13h calls: {count}")
|
||||
# Check for far jumps to unusual addresses
|
||||
if b"\xEA" in boot_code:
|
||||
suspicious_patterns.append("Far JMP instruction found")
|
||||
# Check for self-modifying code patterns
|
||||
if b"\xF3\xA4" in boot_code or b"\xF3\xA5" in boot_code:
|
||||
suspicious_patterns.append("REP MOVSB/MOVSW (memory copy, possible code relocation)")
|
||||
return {
|
||||
"entropy": entropy,
|
||||
"sha256": sha256,
|
||||
"high_entropy": entropy > 6.5,
|
||||
"suspicious_patterns": suspicious_patterns,
|
||||
}
|
||||
|
||||
|
||||
def run_volatility_rootkit_scan(memory_dump, plugin):
|
||||
"""Run a Volatility 3 plugin for rootkit detection via subprocess."""
|
||||
result = subprocess.run(
|
||||
["vol3", "-f", memory_dump, plugin],
|
||||
capture_output=True, text=True,
|
||||
timeout=120,
|
||||
)
|
||||
return result.stdout, result.stderr, result.returncode
|
||||
|
||||
|
||||
def detect_kernel_rootkit(memory_dump):
|
||||
"""Run multiple Volatility plugins to detect kernel-level rootkit artifacts."""
|
||||
plugins = [
|
||||
"windows.ssdt",
|
||||
"windows.callbacks",
|
||||
"windows.driverscan",
|
||||
"windows.modules",
|
||||
"windows.psscan",
|
||||
"windows.pslist",
|
||||
]
|
||||
results = {}
|
||||
for plugin in plugins:
|
||||
stdout, stderr, rc = run_volatility_rootkit_scan(memory_dump, plugin)
|
||||
results[plugin] = {"output": stdout, "error": stderr, "return_code": rc}
|
||||
return results
|
||||
|
||||
|
||||
def compare_process_lists(pslist_output, psscan_output):
|
||||
"""Compare pslist and psscan output to find hidden processes (DKOM)."""
|
||||
pslist_pids = set()
|
||||
psscan_pids = set()
|
||||
for line in pslist_output.splitlines():
|
||||
parts = line.split()
|
||||
if len(parts) >= 2 and parts[1].isdigit():
|
||||
pslist_pids.add(int(parts[1]))
|
||||
for line in psscan_output.splitlines():
|
||||
parts = line.split()
|
||||
if len(parts) >= 2 and parts[1].isdigit():
|
||||
psscan_pids.add(int(parts[1]))
|
||||
hidden = psscan_pids - pslist_pids
|
||||
return hidden
|
||||
|
||||
|
||||
if __name__ == "__main__":
|
||||
print("=" * 60)
|
||||
print("Bootkit & Rootkit Analysis Agent")
|
||||
print("MBR/VBR inspection, UEFI firmware analysis, rootkit detection")
|
||||
print("=" * 60)
|
||||
|
||||
# Demo with a sample MBR file if available
|
||||
demo_mbr = "mbr.bin"
|
||||
if len(sys.argv) > 1:
|
||||
demo_mbr = sys.argv[1]
|
||||
|
||||
if os.path.exists(demo_mbr):
|
||||
print(f"\n[*] Analyzing: {demo_mbr}")
|
||||
mbr = read_mbr(demo_mbr)
|
||||
valid, sig_hex = validate_mbr_signature(mbr)
|
||||
print(f"[*] MBR Signature: 0x{sig_hex.upper()} ({'Valid' if valid else 'INVALID'})")
|
||||
|
||||
partitions = parse_partition_table(mbr)
|
||||
print(f"[*] Partition entries: {len(partitions)}")
|
||||
for p in partitions:
|
||||
active = "Active" if p["active"] else "Inactive"
|
||||
print(f" Part {p['index']}: Type={p['type_id']} {active} "
|
||||
f"Start=LBA {p['start_lba']} Size={p['size_mb']} MB")
|
||||
|
||||
sigs = scan_bootkit_signatures(mbr)
|
||||
for s in sigs:
|
||||
tag = "[*]" if s["clean"] else "[!]"
|
||||
print(f"{tag} Signature match: {s['signature']} at offset {s['offset']}")
|
||||
|
||||
analysis = analyze_boot_code(mbr)
|
||||
print(f"[*] Boot code entropy: {analysis['entropy']}"
|
||||
f" ({'HIGH - possible encryption' if analysis['high_entropy'] else 'Normal'})")
|
||||
print(f"[*] Boot code SHA-256: {analysis['sha256']}")
|
||||
for pat in analysis["suspicious_patterns"]:
|
||||
print(f"[!] {pat}")
|
||||
else:
|
||||
print(f"\n[DEMO] No MBR file provided. Usage: {sys.argv[0]} <mbr.bin | /dev/sda>")
|
||||
print("[DEMO] Provide a 512-byte MBR dump or disk device for analysis.")
|
||||
print("\n[*] Supported analysis:")
|
||||
print(" - MBR/VBR signature validation and bootkit detection")
|
||||
print(" - Partition table parsing and anomaly detection")
|
||||
print(" - Boot code entropy and pattern analysis")
|
||||
print(" - Volatility-based kernel rootkit detection (SSDT, callbacks, DKOM)")
|
||||
print(" - UEFI firmware module inspection via chipsec subprocess")
|
||||
Reference in New Issue
Block a user