CVE-2026-33542 Incus镜像指纹验证缺失漏洞

# Conceptual PoC for CVE-2026-33542 # This script simulates a vulnerable client downloading an image # without verifying the fingerprint against the content hash. import hashlib class VulnerableIncusClient: def download_image(self, image_url, expected_fingerprint): print(f"[*] Downloading image from {image_url}...") # Simulate downloading image content (could be malicious) # In a real attack, this content might be served by a malicious simplestreams server image_content = b"MALICIOUS_CONTAINER_PAYLOAD_HERE" print(f"[*] Expected Fingerprint: {expected_fingerprint}") # VULNERABILITY: The client does NOT calculate the hash of image_content # and compare it with expected_fingerprint. # A secure implementation would do: # actual_hash = hashlib.sha256(image_content).hexdigest() # if actual_hash != expected_fingerprint: # raise Exception("Security Alert: Fingerprint mismatch!") print("[!] VULNERABLE: Storing image to cache without fingerprint verification.") self.cache[image_url] = image_content return True # Usage Example client = VulnerableIncusClient() client.cache = {} # Attacker provides a malicious image but claims it has a legitimate fingerprint client.download_image("http://example.com/image.iso", "sha256:legitimate_image_hash...") print("[!] Exploit successful: Cache poisoned with malicious image.")