FKIE_CVE-2026-31671

Vulnerability from fkie_nvd - Published: 2026-04-24 15:16 - Updated: 2026-11-11 23:10
Summary
In the Linux kernel, the following vulnerability has been resolved: xfrm_user: fix info leak in build_report() struct xfrm_user_report is a __u8 proto field followed by a struct xfrm_selector which means there is three "empty" bytes of padding, but the padding is never zeroed before copying to userspace. Fix that up by zeroing the structure before setting individual member variables.

{
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    },
    {
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          "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)",
          "vendor": "Siemens",
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        {
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      "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
    }
  ],
  "configurations": [
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  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm_user: fix info leak in build_report()\n\nstruct xfrm_user_report is a __u8 proto field followed by a struct\nxfrm_selector which means there is three \"empty\" bytes of padding, but\nthe padding is never zeroed before copying to userspace.  Fix that up by\nzeroing the structure before setting individual member variables."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nxfrm_user: corrige fuga de informaci\u00f3n en build_report()\n\nLa estructura xfrm_user_report es un campo __u8 proto seguido por una estructura xfrm_selector, lo que significa que hay tres bytes de relleno \u2019vac\u00edos\u2019, pero el relleno nunca se pone a cero antes de copiar al espacio de usuario. Se soluciona poniendo a cero la estructura antes de establecer las variables miembro individuales."
    }
  ],
  "id": "CVE-2026-31671",
  "lastModified": "2026-11-11T23:10:00.263",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
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        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
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            {
              "automatable": "no"
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              "technicalImpact": "partial"
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          "role": "CISA Coordinator",
          "timestamp": "2026-11-06T15:23:57.236278Z",
          "version": "2.0.3"
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  "published": "2026-04-24T15:16:46.903",
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  "vulnStatus": "Modified",
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          "lang": "en",
          "value": "CWE-401"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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