{
  "id": "CVE-2021-47218",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2024-04-10T19:15:48.860",
  "lastModified": "2025-01-14T14:44:55.610",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nselinux: fix NULL-pointer dereference when hashtab allocation fails\n\nWhen the hash table slot array allocation fails in hashtab_init(),\nh->size is left initialized with a non-zero value, but the h->htable\npointer is NULL. This may then cause a NULL pointer dereference, since\nthe policydb code relies on the assumption that even after a failed\nhashtab_init(), hashtab_map() and hashtab_destroy() can be safely called\non it. Yet, these detect an empty hashtab only by looking at the size.\n\nFix this by making sure that hashtab_init() always leaves behind a valid\nempty hashtab when the allocation fails."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: selinux: corregir la desreferencia de puntero NULL cuando falla la asignaci\u00f3n de hashtab Cuando la asignaci\u00f3n de la matriz de ranuras de la tabla hash falla en hashtab_init(), h->size se deja inicializado con un valor distinto de cero, pero el puntero h->htable es NULL. Esto puede causar una desreferencia de puntero NULL, ya que el c\u00f3digo policydb se basa en la suposici\u00f3n de que incluso despu\u00e9s de un hashtab_init() fallido, se pueden llamar hashtab_map() y hashtab_destroy() de forma segura. Sin embargo, estos detectan un hashtab vac\u00edo solo mirando el tama\u00f1o. Solucione esto asegur\u00e1ndose de que hashtab_init() siempre deje atr\u00e1s un hashtab vac\u00edo v\u00e1lido cuando falla la asignaci\u00f3n."
    }
  ],
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        "type": "Primary",
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          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6
      }
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          "value": "CWE-476"
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