{
  "id": "CVE-2018-18955",
  "sourceIdentifier": "cve@mitre.org",
  "published": "2018-11-16T20:29:00.233",
  "lastModified": "2020-08-24T17:37:01.140",
  "vulnStatus": "Modified",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel 4.15.x through 4.19.x before 4.19.2, map_write() in kernel/user_namespace.c allows privilege escalation because it mishandles nested user namespaces with more than 5 UID or GID ranges. A user who has CAP_SYS_ADMIN in an affected user namespace can bypass access controls on resources outside the namespace, as demonstrated by reading /etc/shadow. This occurs because an ID transformation takes place properly for the namespaced-to-kernel direction but not for the kernel-to-namespaced direction."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, de las versiones 4.15.x hasta las 4.19.x anteriores a la 4.19.2, map_write() en kernel/user_namespace.c permite el escalado de privilegios debido a que gestiona incorrectamente los espacios de nombre de usuario anidados con m\u00e1s de 5 rangos UID o GID. Un usuario que tenga CAP_SYS_ADMIN en un espacio de nombre de usuario afectado puede omitir los controles de acceso en los recursos fuera del espacio de nombre, tal y como queda demostrado con la lectura de /etc/shadow. Esto ocurre debido a que una transformaci\u00f3n ID ocurre correctamente para la direcci\u00f3n namespaced-to-kernel, pero no para la direcci\u00f3n kernel-to-namespaced."
    }
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          "attackVector": "LOCAL",
          "attackComplexity": "HIGH",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
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