GO-2026-5812: Fleet: Cross-Team Policy Data Exposure via Global Policy Read Endpoint

Fleet is an open-source device management platform built on osquery. In versions prior to 4.85.0, the global policy read endpoint (GET /api/latest/fleet/policies/{policyid}) fails to verify team ownership of the requested policy, allowing an authenticated user with observer-level access on any single team to read the full details of policies belonging to any other team and bypass Fleet's team isolation model. The handler authorizes the request against an empty policy object whose TeamID is nil, which an authorization rule permits for any user holding a role on any team, and then fetches the policy by ID with no team filter and returns it without any post-fetch scope check. Because policy IDs are sequential integers, an attacker can enumerate them to read other teams' policy SQL queries, host pass and fail counts, and associated software-installer and script metadata, exposing security-monitoring strategies and compliance posture across team boundaries. This issue is fixed in version 4.85.0.