CVE-2026-72629 exposes a critical authorization failure in a space-scoped ML deployment platform where three independent attack vectors — inference output extraction, deployment termination, and resource allocation manipulation — all stem from the same root cause: authorization checks were implemented as runtime conventions rather than enforced architectural constraints. The vulnerability allows any user with a valid space ID to access resources in any other space by simply guessing or leaking an identifier, rather than being blocked at the transport or framework layer. The CVSS 7.1 score underweights the compound risk: an attacker who can read model behavior, silently degrade deployments, and trigger availability loss operates a fundamentally different threat class than any single vector captures. The intelligence value of model behavior data — which informs adversarial input construction, extraction attacks, and poisoning strategies — has a longer operational shelf life than typical credential disclosure. This is a CWE-639 (Insecure Direct Object Reference) pattern that has recurred across ecosystems for decades: when authorization is treated as implicit rather than explicit at integration points, the same user-controlled key bypass reproduces through mental model contamination rather than code duplication. The architectural failure isn't just that these three checks were missing — it's that the system allowed new feature layers (inference serving, deployment lifecycle, resource management) to be bolted onto an authorization model designed for an earlier scope without requiring explicit re-verification at each new boundary. Treat authorization as a first-class architectural constraint that must be explicitly extended, not inherited. Implement framework-level enforcement that makes cross-space access structurally impossible rather than relying on runtime checks. Audit all integration points where new features consume existing authorization models — each boundary is a potential recurrence point for this exact pattern.