CVE-2026-53753

{
  "id": "CVE-2026-53753",
  "sourceIdentifier": "[email protected]",
  "published": "2026-06-23T19:17:07.107",
  "lastModified": "2026-10-25T23:10:00.167",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Crawl4AI is an open-source LLM friendly web crawler & scraper. Prior to 0.8.7, the _safe_eval_expression() function in the computed fields feature uses an AST validator that only blocks attributes starting with underscore. Python generator and frame object attributes (gi_frame, f_back, f_builtins) do NOT start with underscore, enabling a complete sandbox escape to achieve arbitrary code execution. The attack requires no authentication (JWT disabled by default) and is triggered via POST /crawl with a crafted extraction schema. This vulnerability is fixed in 0.8.7."
    },
    {
      "lang": "es",
      "value": "Crawl4AI es un rastreador y extractor web de código abierto compatible con LLM. Antes de la versión 0.8.7, la función _safe_eval_expression() en la característica de campos calculados utiliza un validador AST que solo bloquea atributos que comienzan con guion bajo. Los atributos de objeto de generador y de marco de Python (gi_frame, f_back, f_builtins) NO comienzan con guion bajo, lo que permite un escape completo del sandbox para lograr ejecución de código arbitrario. El ataque no requiere autenticación (JWT deshabilitado por defecto) y se activa a través de POST /crawl con un esquema de extracción manipulado. Esta vulnerabilidad está corregida en 0.8.7."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "unclecode",
          "product": "crawl4ai",
          "versions": [
            {
              "version": "< 0.8.7",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9
      },
      {
        "source": "[email protected]",
        "type": "Primary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
          "baseScore": 10.0,
          "baseSeverity": "CRITICAL",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 6.0
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-06-23T18:55:14.019870Z",
          "id": "CVE-2026-53753",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-94"
        },
        {
          "lang": "en",
          "value": "CWE-913"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:kidocode:crawl4ai:*:*:*:*:*:*:*:*",
              "versionEndExcluding": "0.8.7",
              "matchCriteriaId": "5C153B68-AA3F-4755-BA13-E98AAB321695"
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  ],
  "references": [
    {
      "url": "https://github.com/unclecode/crawl4ai/security/advisories/GHSA-qxjp-w3pj-48m7",
      "source": "[email protected]",
      "tags": [
        "Third Party Advisory",
        "Mitigation"
      ]
    },
    {
      "url": "https://github.com/unclecode/crawl4ai/security/advisories/GHSA-qxjp-w3pj-48m7",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "Third Party Advisory",
        "Mitigation"
      ]
    }
  ]
}