resettable-memo-nonce-review

Availability: opt-in. Severity: info. Confidence: high.

The initial scope is Map<Bytes<32>, List<Bytes<32>>>. The selected immutable key must equal the active account recipient's represented ZswapCoinPublicKey.bytes, through source operands or required successful equalities. Exact immutable lookup operands identify the source and destination within a history. A shared wildcard storage path never establishes their equality. Dynamic keys in separate entry histories establish only reset may-overlap; distinct literal reset selectors do not qualify. Replacements proven to target an absent slot or already-empty current List do not establish a restart; unknown initial storage is not assumed empty. An acknowledged nonzero count can still reset the extent and remains in scope.

Select the rule explicitly:

{"version":1,"detectors":["resettable-memo-nonce-review"]}

No memo or encryption purpose is inferred from a List name or stored bytes. The finding states that the same resettable extent supplies both a canonical coin nonce and a directly stored evolved payload. Its protocol role requires review. An opaque payload does not represent memo construction or encryption use. An arbitrary stored hash, encoded index, nonce identifier or marker does not establish the paired relation. Fresh seeds, mixed/arithmetic indices, transformed payloads, noncanonical namesakes, another append receiver, different source revisions, exclusive histories and aborted resets do not qualify. Root Lists, nested Maps, contract recipients and unconstrained recipient relations are outside this narrow review.

Quiet output concerns this paired relation only. In particular, a fresh coin nonce alongside a resettable length-derived stored payload is quiet because one consumer is independent; it does not establish memo uniqueness. An independent Counter used for both consumers avoids this paired resettable-length relationship.

The rule does not establish actual recurrence, successful transactions, one-time pad use, encryption/decryption, confidentiality impact, authorization intent or production implementation correspondence. Use of a resettable extent is not by itself proof that a stored value requires security randomness. Severity remains informational and default activation is unchanged.