--- cve: "CVE-2026-89186" severity: "MEDIUM" cvss: 6.3 epss: "39%" vendor: "ZenHive" kev: false exploited: false published: "2026-09-16 09:17:07" tags: [cve, security, medium] source: tsecurity.de CVE-Dossier exported: "2026-09-18T10:32:45+02:00" --- # CVE-2026-89186 > 6.3 MEDIUM · 🧪 PoC ## Beschreibung 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-Vektor ``` CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N ``` | Metrik | Wert | Bewertung | |---|---|---| | AV Angriffsvektor | Netzwerk | bad | | AC Komplexität | Gering | bad | | PR Privilegien | Keine | bad | | UI Interaktion | Keine | bad | ## Patch verfügbar (OSV) - 3b7e43abf60fa30c40985e4043965ec67791b4dc (Commit) ## Referenzen - - - - - --- _Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-89186) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_