{
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        "metrics": [
          {
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              "content": {
                "id": "CVE-2026-48714",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-16T14:50:19.973996Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-16T14:50:29.087Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "i18next-http-middleware",
          "vendor": "i18next",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 3.9.7"
            }
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          "lang": "en",
          "value": "i18next-http-middleware is a middleware to be used with Node.js web frameworks like express or Fastify and also for Deno. In versions prior to 3.9.7, the missingKeyHandler blocked the literal request-body keys __proto__, constructor, and prototype (added in 3.9.3, see GHSA-5fgg-jcpf-8jjw), but did not reject dotted variants such as \"__proto__.polluted\". Downstream backends that split the missing-key string on a configured keySeparator (notably i18next-fs-backend \u2264 2.6.5) hand these keys to an unguarded setPath() walker that writes to Object.prototype. Applications that expose missingKeyHandler to untrusted input AND use i18next-fs-backend \u2264 2.6.5 are directly exploitable for remote prototype pollution. Other downstream backends that split the missing-key string the same way may be similarly affected. Depending on the host application, polluted prototype properties may cause crashes, corrupted translation behaviour, configuration poisoning, or bypasses of property-based security checks. This issue has been fixed in version 3.9.7.  If developers cannot upgrade immediately, they should do the following: do not expose missingKeyHandler to untrusted users (mount it behind authentication, or remove the route), add a request-body filter ahead of the handler that rejects any top-level key containing __proto__, constructor, or prototype after splitting on their configured keySeparator, and disable missing-key persistence (saveMissing: false) when accepting writes from untrusted input."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.1,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "NONE",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-1321",
              "description": "CWE-1321: Improperly Controlled Modification of Object Prototype Attributes (\u0027Prototype Pollution\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-15T20:41:49.382Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/i18next/i18next-http-middleware/security/advisories/GHSA-f49m-vf83-692w",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/i18next/i18next-http-middleware/security/advisories/GHSA-f49m-vf83-692w"
        },
        {
          "name": "https://github.com/i18next/i18next-http-middleware/commit/7c6d26f137d3e940b8d229ca148bca38845faf49",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/i18next/i18next-http-middleware/commit/7c6d26f137d3e940b8d229ca148bca38845faf49"
        }
      ],
      "source": {
        "advisory": "GHSA-f49m-vf83-692w",
        "discovery": "UNKNOWN"
      },
      "title": "i18next-http-middleware missingKeyHandler does not reject keys whose segments contain prototype-polluting names"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
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    "datePublished": "2026-06-15T20:41:49.382Z",
    "dateReserved": "2026-05-22T18:47:27.755Z",
    "dateUpdated": "2026-06-16T14:50:29.087Z",
    "state": "PUBLISHED"
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  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-48714",
      "date": "2026-06-16",
      "epss": "0.0038",
      "percentile": "0.2967"
    },
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