CVE-2026-40097 Step CA 拒绝服务漏洞

import os import sys # This script demonstrates the concept of triggering CVE-2026-40097. # The vulnerability is triggered by sending a TPM Attestation Key (AK) certificate # with an empty Extended Key Usage (EKU) extension to a vulnerable Step CA server. def generate_exploit_concept(): print("[+] Concept for CVE-2026-40097 PoC") print("[+] Target: Step CA < 0.30.0-rc3 with TPM attestation enabled") print("[+] Mechanism: Send AK cert with empty EKU extension (ASN.1 SEQUENCE length 0)") # In a real exploit, one would use an ASN.1 library to construct a certificate # where the EKU extension (OID 2.5.29.37) contains an empty sequence. # Example raw bytes for the EKU extension value: # 0x30 0x00 (SEQUENCE, length 0) exploit_payload_description = """ Malformed Certificate Structure: - Subject: ... - Extensions: - Extended Key Usage: <EMPTY SEQUENCE> (Normally contains OIDs like 2.23.133.8.3 for AIK) """ print(exploit_payload_description) print("[+] Sending this certificate during ACME 'device-attest-01' challenge will cause a panic.") if __name__ == "__main__": generate_exploit_concept()