Adversaries look for the complete crypto picture: algorithms and modes, key types and lifecycles, authentication schemes, counter or time-tag handling, anti-replay windows, link-layer protections, and any differences between uplink and downlink policy. With algorithm and key details, a threat actor can craft valid telecommands, masquerade as a trusted endpoint, or degrade availability through replay and desynchronization. Sources include interface specifications, ground software logs, test vectors, configuration files, contractor laptops, and payload-specific ICDs that reuse bus-level credentials. Particular risk arises when command links rely on authentication without confidentiality; once an adversary acquires the necessary keys or counters, they can issue legitimate-looking commands outside official channels. Programs should assume that partial disclosures, MAC length, counter reset rules, or key rotation cadence, aid exploitation.