CVE-2026-31221

{
  "id": "CVE-2026-31221",
  "sourceIdentifier": "[email protected]",
  "published": "2026-05-12T16:16:14.020",
  "lastModified": "2026-11-08T16:10:00.183",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "PyTorch-Lightning versions 2.6.0 and earlier contain an insecure deserialization vulnerability (CWE-502) in the checkpoint loading mechanism. The LightningModule.load_from_checkpoint() method, which is commonly used to load saved model states, internally calls torch.load() without setting the security-restrictive weights_only=True parameter. This default behavior allows the deserialization of arbitrary Python objects via the Pickle module. A remote attacker can exploit this by providing a maliciously crafted checkpoint file, leading to arbitrary code execution on the victim's system when the file is loaded."
    },
    {
      "lang": "es",
      "value": "Las versiones 2.6.0 y anteriores de PyTorch-Lightning contienen una vulnerabilidad de deserialización insegura (CWE-502) en el mecanismo de carga de puntos de control. El método LightningModule.load_from_checkpoint(), que se usa comúnmente para cargar estados de modelos guardados, llama internamente a torch.load() sin establecer el parámetro de restricción de seguridad weights_only=True. Este comportamiento predeterminado permite la deserialización de objetos Python arbitrarios a través del módulo Pickle. Un atacante remoto puede explotar esto al proporcionar un archivo de punto de control creado maliciosamente, lo que lleva a la ejecución de código arbitrario en el sistema de la víctima cuando se carga el archivo."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "n/a",
          "product": "n/a",
          "versions": [
            {
              "version": "n/a",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
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      {
        "source": "[email protected]",
        "type": "Primary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "REQUIRED",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9
      },
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        "type": "Secondary",
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          "baseScore": 8.8,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "REQUIRED",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-05-15T18:02:25.761345Z",
          "id": "CVE-2026-31221",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
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  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
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          "lang": "en",
          "value": "CWE-502"
        }
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    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary",
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  "configurations": [
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          "cpeMatch": [
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  "references": [
    {
      "url": "https://github.com/Lightning-AI/pytorch-lightning",
      "source": "[email protected]",
      "tags": [
        "Product"
      ]
    },
    {
      "url": "https://www.notion.so/CVE-2026-31221-35d1e1393188815f8db7c4fd08076639",
      "source": "[email protected]",
      "tags": [
        "Exploit",
        "Third Party Advisory"
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}