FKIE_CVE-2021-41556

Vulnerability from fkie_nvd - Published: 2022-07-28 21:15 - Updated: 2026-06-17 04:08
Severity
10.0 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
10.0 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Summary
sqclass.cpp in Squirrel through 2.2.5 and 3.x through 3.1 allows an out-of-bounds read (in the core interpreter) that can lead to Code Execution. If a victim executes an attacker-controlled squirrel script, it is possible for the attacker to break out of the squirrel script sandbox even if all dangerous functionality such as File System functions has been disabled. An attacker might abuse this bug to target (for example) Cloud services that allow customization via SquirrelScripts, or distribute malware through video games that embed a Squirrel Engine.
References
cve@mitre.orghttp://www.squirrel-lang.org/#downloadThird Party Advisory
cve@mitre.orghttps://blog.sonarsource.com/squirrel-vm-sandbox-escape/Exploit, Third Party Advisory
cve@mitre.orghttps://github.com/albertodemichelis/squirrel/commit/23a0620658714b996d20da3d4dd1a0dcf9b0bd98Patch, Third Party Advisory
cve@mitre.orghttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BV7SJJ44AGAX4ILIVPREIXPJ2GOG3FKV/
cve@mitre.orghttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/M3FQILX7UUEERSDPMZP3MKGTMY2E7ESU/
af854a3a-2127-422b-91ae-364da2661108http://www.squirrel-lang.org/#downloadThird Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://blog.sonarsource.com/squirrel-vm-sandbox-escape/Exploit, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/albertodemichelis/squirrel/commit/23a0620658714b996d20da3d4dd1a0dcf9b0bd98Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BV7SJJ44AGAX4ILIVPREIXPJ2GOG3FKV/
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/M3FQILX7UUEERSDPMZP3MKGTMY2E7ESU/
134c704f-9b21-4f2e-91b3-4a467353bcc0https://www.sonarsource.com/blog/squirrel-vm-sandbox-escape/
Impacted products
Vendor Product Version
squirrel-lang squirrel *
squirrel-lang squirrel *
fedoraproject fedora 35
fedoraproject fedora 36
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "source": "cve@mitre.org"
    }
  ],
  "configurations": [
    {
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  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "sqclass.cpp in Squirrel through 2.2.5 and 3.x through 3.1 allows an out-of-bounds read (in the core interpreter) that can lead to Code Execution. If a victim executes an attacker-controlled squirrel script, it is possible for the attacker to break out of the squirrel script sandbox even if all dangerous functionality such as File System functions has been disabled. An attacker might abuse this bug to target (for example) Cloud services that allow customization via SquirrelScripts, or distribute malware through video games that embed a Squirrel Engine."
    },
    {
      "lang": "es",
      "value": "El archivo sqclass.cpp en Squirrel versiones hasta 2.2.5 y 3.x hasta 3.1 permite una lectura fuera de l\u00edmites (en el int\u00e9rprete del n\u00facleo) que puede conllevar a una ejecuci\u00f3n de c\u00f3digo. Si una v\u00edctima ejecuta un script de Squirrel controlado por un atacante, es posible que el atacante salga del sandbox del script de Squirrel incluso si toda la funcionalidad peligrosa, como las funciones del sistema de archivos, ha sido deshabilitada. Un atacante podr\u00eda abusar de este fallo para dirigirse (por ejemplo) a servicios en la nube que permitan la personalizaci\u00f3n por medio de SquirrelScripts, o distribuir malware mediante videojuegos que incorporen un Squirrel Engine"
    }
  ],
  "id": "CVE-2021-41556",
  "lastModified": "2026-06-17T04:08:38.493",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 10.0,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
          "version": "3.1"
        },
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        "impactScore": 6.0,
        "source": "nvd@nist.gov",
        "type": "Primary"
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          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
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          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
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        "type": "Secondary"
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    "ssvcV203": [
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        "ssvcData": {
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          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-05-29T18:48:35.079402Z",
          "version": "2.0.3"
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  "published": "2022-07-28T21:15:08.057",
  "references": [
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      "tags": [
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    },
    {
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      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/M3FQILX7UUEERSDPMZP3MKGTMY2E7ESU/"
    },
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      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/M3FQILX7UUEERSDPMZP3MKGTMY2E7ESU/"
    },
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  "vulnStatus": "Modified",
  "weaknesses": [
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      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}



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