Use of Cache Containing Sensitive Information in ZenHive mpp allows a shared HTTP cache to store a paid response and serve it to clients that never paid.
MPP.Plug.verify_credential in lib/mpp/plug.ex sets payment-receipt and cache-control: private on the connection before the wrapped application runs, and registers no register_before_send/2 callback. Plug.Conn.put_resp_header/3 replaces an existing header, so a mounting application that sets its own cache-control on the paid resource (for example public, max-age=3600) silently overrides the private the library relies on, and a CDN or reverse proxy can then store the paid 200 together with its Payment-Receipt and serve both to unpaid clients. The library-level guarantee is therefore defeatable by the application it protects. For the same reason a downstream non-2xx response still carried Payment-Receipt, issuing a receipt for a response that delivered no resource.
This issue affects mpp: from 0.1.0 before 0.16.2.
CVSS
No CVSS.
References
Configurations
No configuration.
History
No history.
Information
Published : 2026-09-16 09:17
Updated : 2026-09-16 15:18
NVD link : CVE-2026-89186
Mitre link : CVE-2026-89186
CVE.ORG link : CVE-2026-89186
JSON object : View
Products Affected
No product.
CWE
CWE-524
Use of Cache Containing Sensitive Information