{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2025-62496",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-10-16T17:26:14.998141Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-10-16T17:26:25.654Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://bellard.org/quickjs/",
          "defaultStatus": "unaffected",
          "packageName": "js_bigint_from_string",
          "product": "QuickJS",
          "vendor": "QuickJS",
          "versions": [
            {
              "lessThan": "2025-09-13",
              "status": "affected",
              "version": "2025-04-26",
              "versionType": "date"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Google Big Sleep"
        }
      ],
      "datePublic": "2025-07-24T22:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
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              "type": "text/html",
              "value": "\u003cp\u003eA vulnerability exists in the QuickJS engine\u0027s BigInt string parsing logic (\u003ccode\u003ejs_bigint_from_string\u003c/code\u003e) when attempting to create a BigInt from a string with an \u003cb\u003eexcessively large number of digits\u003c/b\u003e.\u003c/p\u003e\u003cp\u003eThe function calculates the necessary number of bits (\u003ccode\u003en_bits\u003c/code\u003e) required to store the BigInt using the formula:\u003c/p\u003e\u003cdiv\u003e$$\\text{n\\_bits} = (\\text{n\\_digits} \\times 27 + 7) / 8 \\quad (\\text{for radix 10})$$\u003c/div\u003e\u003col\u003e\u003cli\u003e\u003cp\u003eFor large input strings (e.g., $79,536,432$ digits or more for base 10), the intermediate calculation $(\\text{n\\_digits} \\times 27 + 7)$ exceeds the maximum value of a standard signed 32-bit integer, resulting in an \u003cb\u003eInteger Overflow\u003c/b\u003e.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eThe resulting \u003ccode\u003en_bits\u003c/code\u003e value becomes unexpectedly small or even \u003cb\u003enegative\u003c/b\u003e due to this wrap-around.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eThis flawed \u003ccode\u003en_bits\u003c/code\u003e is then used to compute \u003ccode\u003en_limbs\u003c/code\u003e, the number of memory \"limbs\" needed for the BigInt object. Since \u003ccode\u003en_bits\u003c/code\u003e is too small, the calculated \u003ccode\u003en_limbs\u003c/code\u003e is also \u003cb\u003esignificantly underestimated\u003c/b\u003e.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eThe function proceeds to allocate a \u003cb\u003e\u003ccode\u003eJSBigInt\u003c/code\u003e\u003c/b\u003e object using this underestimated \u003ccode\u003en_limbs\u003c/code\u003e.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eWhen the function later attempts to write the actual BigInt data into the allocated object, the small buffer size is quickly exceeded, leading to a \u003cb\u003eHeap Out-of-Bounds Write\u003c/b\u003e as data is written past the end of the allocated \u003ccode\u003er-\u0026gt;tab\u003c/code\u003e array.\u003c/p\u003e\u003c/li\u003e\u003c/ol\u003e\u003cbr\u003e"
            }
          ],
          "value": "A vulnerability exists in the QuickJS engine\u0027s BigInt string parsing logic (js_bigint_from_string) when attempting to create a BigInt from a string with an excessively large number of digits.\n\nThe function calculates the necessary number of bits (n_bits) required to store the BigInt using the formula:\n\n$$\\text{n\\_bits} = (\\text{n\\_digits} \\times 27 + 7) / 8 \\quad (\\text{for radix 10})$$\n\n  *  For large input strings (e.g., $79,536,432$ digits or more for base 10), the intermediate calculation $(\\text{n\\_digits} \\times 27 + 7)$ exceeds the maximum value of a standard signed 32-bit integer, resulting in an Integer Overflow.\n\n\n  *  The resulting n_bits value becomes unexpectedly small or even negative due to this wrap-around.\n\n\n  *  This flawed n_bits is then used to compute n_limbs, the number of memory \"limbs\" needed for the BigInt object. Since n_bits is too small, the calculated n_limbs is also significantly underestimated.\n\n\n  *  The function proceeds to allocate a JSBigInt object using this underestimated n_limbs.\n\n\n  *  When the function later attempts to write the actual BigInt data into the allocated object, the small buffer size is quickly exceeded, leading to a Heap Out-of-Bounds Write as data is written past the end of the allocated r-\u003etab array."
        }
      ],
      "impacts": [
        {
          "capecId": "CAPEC-175",
          "descriptions": [
            {
              "lang": "en",
              "value": "CAPEC-175 Code Inclusion"
            }
          ]
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "HIGH",
            "attackRequirements": "PRESENT",
            "attackVector": "ADJACENT",
            "baseScore": 7.1,
            "baseSeverity": "HIGH",
            "privilegesRequired": "LOW",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "LOW",
            "subConfidentialityImpact": "HIGH",
            "subIntegrityImpact": "HIGH",
            "userInteraction": "PASSIVE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:A/AC:H/AT:P/PR:L/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L",
            "version": "4.0",
            "vulnAvailabilityImpact": "LOW",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-190",
              "description": "CWE-190 Integer Overflow or Wraparound",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-10-16T15:52:05.654Z",
        "orgId": "14ed7db2-1595-443d-9d34-6215bf890778",
        "shortName": "Google"
      },
      "references": [
        {
          "url": "https://bellard.org/quickjs/Changelog"
        },
        {
          "url": "https://issuetracker.google.com/434193016"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "Integer overflow in js_bigint_from_string in QuickJS",
      "x_generator": {
        "engine": "Vulnogram 0.2.0"
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  "cveMetadata": {
    "assignerOrgId": "14ed7db2-1595-443d-9d34-6215bf890778",
    "assignerShortName": "Google",
    "cveId": "CVE-2025-62496",
    "datePublished": "2025-10-16T15:52:05.654Z",
    "dateReserved": "2025-10-15T08:47:41.878Z",
    "dateUpdated": "2025-10-16T17:26:25.654Z",
    "state": "PUBLISHED"
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  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}