CVE-2026-39956

{
  "id": "CVE-2026-39956",
  "sourceIdentifier": "[email protected]",
  "published": "2026-04-13T23:16:27.653",
  "lastModified": "2026-10-26T21:10:00.170",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "jq is a command-line JSON processor. Prior to version 1.8.2, the _strindices builtin in jq's src/builtin.c passes its arguments directly to jv_string_indexes() without verifying they are strings, and jv_string_indexes() in src/jv.c relies solely on assert() checks that are stripped in release builds compiled with -DNDEBUG. This allows an attacker to crash jq trivially with input like _strindices(0), and by crafting a numeric value whose IEEE-754 bit pattern maps to a chosen pointer, achieve a controlled pointer dereference and limited memory read/probe primitive. Any deployment that evaluates untrusted jq filters against a release build is vulnerable. This issue has been patched in commit fdf8ef0f0810e3d365cdd5160de43db46f57ed03, which is part of version 1.8.2."
    },
    {
      "lang": "es",
      "value": "jq es un procesador JSON de línea de comandos. En commits posteriores a 69785bf77f86e2ea1b4a20ca86775916889e91c9, la función _strindices incorporada en src/builtin.c de jq pasa sus argumentos directamente a jv_string_indexes() sin verificar que sean cadenas, y jv_string_indexes() en src/jv.c se basa únicamente en comprobaciones assert() que se eliminan en las compilaciones de lanzamiento compiladas con -DNDEBUG. Esto permite a un atacante bloquear jq trivialmente con una entrada como _strindices(0), y al elaborar un valor numérico cuyo patrón de bits IEEE-754 se mapea a un puntero elegido, lograr una desreferencia de puntero controlada y una primitiva limitada de lectura/sondeo de memoria. Cualquier despliegue que evalúe filtros jq no confiables contra una compilación de lanzamiento es vulnerable. Este problema ha sido parcheado en el commit fdf8ef0f0810e3d365cdd5160de43db46f57ed03."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "jqlang",
          "product": "jq",
          "versions": [
            {
              "version": "< 1.8.2",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H",
          "baseScore": 6.1,
          "baseSeverity": "MEDIUM",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "REQUIRED",
          "scope": "UNCHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 4.2
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-04-14T15:34:20.696741Z",
          "id": "CVE-2026-39956",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        },
        {
          "lang": "en",
          "value": "CWE-476"
        },
        {
          "lang": "en",
          "value": "CWE-843"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:jqlang:jq:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "2026-04-02",
              "versionEndExcluding": "2026-04-08",
              "matchCriteriaId": "268F5CFD-46C6-4090-A7CD-F85927DE3B70"
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  "references": [
    {
      "url": "https://github.com/jqlang/jq/commit/fdf8ef0f0810e3d365cdd5160de43db46f57ed03",
      "source": "[email protected]",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://github.com/jqlang/jq/security/advisories/GHSA-6gc3-3g9p-xx28",
      "source": "[email protected]",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://github.com/jqlang/jq/security/advisories/GHSA-6gc3-3g9p-xx28",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "Exploit",
        "Vendor Advisory"
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  ]
}