MONAI model download verification reported success with no expected hash

MONAI check_hash returned a successful result when the expected digest argument was None, despite documentation presenting the operation as an integrity check.

The weak state arises when a model or dataset retrieval call lacks a pinned hash and an adversary can modify the downloaded bytes. A substituted model artifact could pass a nominal hash-checking step without actually being authenticated against known content.

The advisory does not establish an exploited hospital download, and the possible chain to executable bundle logging has not been observed. Require an actual trusted expected digest or signed manifest for every artifact and reject verification calls without a usable trust anchor.

Evidence interpretation and control boundary. An integrity-check function returning success with no expected digest is not proof that the downloaded artifact matches a trusted publisher. A caller would need a controlled download or substituted artifact for this to become an attack, and the separately reported executable logging configuration creates a possible compound path, not an observed exploit chain. A real verifier must fail closed on absent hashes or validate an independent signed manifest.