The codec-ohttp implementation of draft-ietf-ohai-chunked-ohttp does not verify that a cryptographically-signed final chunk was received before the outer HTTP body terminates. An on-path adversary (the OHTTP relay itself, or any MITM on the relay↔gateway or relay↔client transport) can forward a prefix of a legitimate chunked-OHTTP message—cut at a non-final chunk boundary—and close the outer body cleanly, producing no decryption error and no exception in the receiving application.