{"id":"CVE-2026-89186","title":"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.\n\nMPP.Plug.verify_credential in lib/mpp/plug.ex sets payment-receipt and cache-contr…","summary":"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.\n\nMPP.Plug.verify_credential in lib/mpp/plug.ex sets payment-receipt and cache-contr…","severity":"medium","cvss":6.3,"cvssVector":"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","cwe":["CWE-524"],"vendor":"ZenHive","product":"mpp","affected":["mpp >= 0.1.0 < 0.16.2","zenhive/mpp >= 2d4d1d94aae7790ae0623063961adbeef171fa71 < 2fd91a5ecbd0b0ad2a4ac202b79659e8126dbc0b"],"published":"2026-09-16","updated":"2026-09-16","sourceUpdated":"2026-09-16T20:38:33.883","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-89186","references":[{"url":"https://cna.erlef.org/cves/CVE-2026-89186.html","label":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db"},{"url":"https://github.com/ZenHive/mpp/commit/2d4d1d94aae7790ae0623063961adbeef171fa71","label":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db"},{"url":"https://github.com/ZenHive/mpp/commit/2fd91a5ecbd0b0ad2a4ac202b79659e8126dbc0b","label":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db"},{"url":"https://github.com/ZenHive/mpp/security/advisories/GHSA-82qh-vrvm-gqvc","label":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db"},{"url":"https://osv.dev/vulnerability/EEF-CVE-2026-89186","label":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db"}],"tags":["nvd","cve.org"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-09-16T14:50:34.541725Z"},"cvssSource":"cna","ingestedAt":"2026-09-16T08:52:29.600Z","epss":0.00394,"epssPercentile":0.33393,"slug":"CVE-2026-89186","body":"## Overview\n\nUse 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.\n\nMPP.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.\n\nThis issue affects mpp: from 0.1.0 before 0.16.2.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":35,"depthScoreParts":{"impact":34.7,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}