[Agricola] AGR-2026-044: Body-aware successful responses lack private cache control

[mpp-agricola]

AGR-2026-044 — Body-aware successful responses lack private cache control

Last observed by the head-to-head audit at 2026-08-10T09:38:20.026276Z.

Audited heads

Target	Repository	Commit	Conformance	Semantic review
typescript	wevm/mppx	b7ab48e38e3d	Complete	Reference
rust	tempoxyz/mpp-rs	28c704988b3d	Complete	Complete
go	tempoxyz/mpp-go	266810add451	Complete	Complete
java	stripe/mpp-java	bc52e0f5c77b	Complete	Complete
python	tempoxyz/pympp	09b449739221	Complete	Complete
ruby	stripe/mpp-rb	58a98bbf6820	Complete	Complete

Finding

• Fingerprint: semantic:http-caching/receipt-response-is-private
• Source: semantic
• Affected SDKs: rust
• Clean SDKs: none
• Not reported by semantic review: go, java, python, ruby
• Canonical reference: draft-httpauth-payment-00 § Caching
• Severity: medium
• Confidence: high

Evidence

SDK	Canonical evidence	SDK evidence	Suggested test
rust	http().respondReceipt — Adds private to the response's Cache-Control directives whenever it attaches Payment-Receipt.	PaymentBodyService::call — Attaches Payment-Receipt after successful body-bound verification but returns the application response without adding private to Cache-Control.	Pass a valid body-bound credential through PaymentBodyLayer with an inner response using Cache-Control: max-age=60; assert the result has Payment-Receipt and Cache-Control containing both max-age=60 and private.

rust: The target's body-aware middleware attaches Payment-Receipt but does not add Cache-Control: private. A shared intermediary may therefore cache a response containing sensitive receipt data, unlike canonical behavior.

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Target	Automation	Status	Pull request
rust	pr	Recorded	tempoxyz/mpp-rs#381

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/ag fix

Command	What it does
/ag fix	Opens or retries draft fixes for every affected PR-enabled SDK.
/ag fix rust	Opens or retries the draft fix for rust only.
/ag fix "instruction"	Applies the instruction to affected fixes; recorded PRs also incorporate unresolved review feedback and failed CI.
/ag status	Reports the current state of linked remediation pull requests.

[brendanjryan]

/ag fix

[mpp-agricola]

Queued remediation for rust.

View fix run

[mpp-agricola]

Opened draft PR for rust: tempoxyz/mpp-rs#381.

View fix run