{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0.14.0"
              },
              {
                "fixed": "0.16.2"
              }
            ],
            "source": [
              "DESCRIPTION",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "ad394b7df40e014eefb9f2f5ca2127326a005c3f"
            },
            {
              "fixed": "3b7e43abf60fa30c40985e4043965ec67791b4dc"
            },
            {
              "fixed": "4b6eaec02af0e8485cfb4ff68f467d075ed5dd6f"
            },
            {
              "fixed": "db464dfa9a86ccda58f0827101f6da6bd8aafa78"
            }
          ],
          "repo": "https://github.com/zenhive/mpp",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-p9fv-9w58-95x2"
  ],
  "database_specific": {
    "cna_assigner": "EEF",
    "cwe_ids": [
      "CWE-294"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/87xxx/CVE-2026-87119.json",
    "unresolved_ranges": [
      {
        "extracted_events": [
          {
            "introduced": "db464dfa9a86ccda58f0827101f6da6bd8aafa78"
          },
          {
            "fixed": "4b6eaec02af0e8485cfb4ff68f467d075ed5dd6f"
          }
        ],
        "source": "AFFECTED_FIELD"
      }
    ]
  },
  "details": "Authentication Bypass by Capture-replay in ZenHive mpp allows an attacker holding a captured subscription activation credential to charge the payer repeatedly.\n\nThe payer signs a Tempo KeyAuthorization over the chain id, key type, key id, expiry, limits and scopes only, with nothing tying it to the challenge that prompted it. MPP.Methods.Tempo.KeyAuthorization.verify/3 in lib/mpp/methods/tempo/key_authorization.ex pins each of those signed fields against the subscription request, and the access key it pins is a static per-endpoint server key, so one signed authorization verifies against every challenge the server issues for the same subscription terms. MPP.Methods.Tempo.Subscription.activate/4 deduplicates activations by challenge id, so presenting the captured credential under a fresh challenge produces a different dedup key, claim_activation succeeds, and the subscription transaction is built and broadcast again. Each replay charges the payer's wallet a new first-period settlement and re-authorizes the server key, bounded only by the subscription expiry and the chain's own semantics for re-installing an existing key.\n\nThis issue affects mpp: from 0.14.0 before 0.16.2.",
  "id": "CVE-2026-87119",
  "modified": "2026-09-24T03:30:59.488374255Z",
  "published": "2026-09-22T11:16:56.232Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://cna.erlef.org/cves/CVE-2026-87119.html"
    },
    {
      "type": "WEB",
      "url": "https://github.com"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/EEF-CVE-2026-87119"
    },
    {
      "type": "WEB",
      "url": "https://repo.hex.pm"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/87xxx/CVE-2026-87119.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/ZenHive/mpp/security/advisories/GHSA-p9fv-9w58-95x2"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-87119"
    },
    {
      "type": "FIX",
      "url": "https://github.com/ZenHive/mpp/commit/4b6eaec02af0e8485cfb4ff68f467d075ed5dd6f"
    },
    {
      "type": "FIX",
      "url": "https://github.com/ZenHive/mpp/commit/db464dfa9a86ccda58f0827101f6da6bd8aafa78"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/ZenHive/mpp"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "mpp Tempo subscription key authorization is not bound to the issuing challenge, allowing a captured activation credential to be replayed"
}