CVE-2026-40622

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Una \u00fanica consulta NS de cliente puede hacer que Unbound sobrescriba el conjunto de registros NS de referencia del lado del padre caducado en cach\u00e9 con el conjunto de registros NS de \u00e1pice del lado del hijo y esencialmente extender la ventana de dominio fantasma hasta un valor configurado de TTL en cach\u00e9 ('cache-max-ttl'). En configuraciones donde se usa 'harden-referral-path: yes' (configuraci\u00f3n no predeterminada), no se requiere ninguna consulta NS de cliente ya que Unbound realiza impl\u00edcitamente esa consulta. 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