Vulnerabilities > CVE-2018-8409 - Unspecified vulnerability in Microsoft .Net Core, Asp.Net Core and System.Io.Pipelines

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from the Microsoft Security Updates API. The text
# itself is copyright (C) Microsoft Corporation.
#
include("compat.inc");

if (description)
{
  script_id(117481);
  script_version("1.6");
  script_cvs_date("Date: 2019/11/01");

  script_cve_id("CVE-2018-8409");
  script_bugtraq_id(105223);

  script_name(english:"Security Updates for Microsoft .NET core and ASP.NET Core (DoS) (September 2018)");
  script_summary(english:"Checks the version of ASP.NET Core packages.");

  script_set_attribute(attribute:"synopsis", value:
"The Microsoft ASP.NET Core installations on the remote host contain vulnerable packages..");
  script_set_attribute(attribute:"description", value:
"The Microsoft ASP.NET Core installation on the remote host contains 
vulnerable packages. It is, therefore,affected by a Denial of Service 
vulnerability.");
  # https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-8409
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?ffb9c6e3");
  # https://blogs.msdn.microsoft.com/dotnet/2018/09/11/net-core-september-2018-update/
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?08628312");
  script_set_attribute(attribute:"see_also", value:"https://github.com/aspnet/announcements/issues/316");
  script_set_attribute(attribute:"see_also", value:"https://github.com/dotnet/announcements/issues/83");
  script_set_attribute(attribute:"solution", value:
"Update ASP.NET Core, remove vulnerable packages and refer to vendor advisory.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2018-8409");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/09/11");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/09/11");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/09/13");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:microsoft:aspnet_core");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Windows : Microsoft Bulletins");

  script_copyright(english:"This script is Copyright (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("microsoft_asp_dotnet_core_win.nbin");
  script_require_ports(139, 445);

  exit(0);
}

include("global_settings.inc");
include("audit.inc");
include("install_func.inc");
include("misc_func.inc");
include("smb_func.inc");
include("vcf.inc");

appname = 'ASP .NET Core Windows';
package_dat = {
  'Microsoft.AspNetCore.All':{
    'constraints':[
      { "min_version" : "2.1.0", "fixed_version" : "2.1.4" }
    ],
    'instances':make_list()
  },
  'Microsoft.AspNetCore.App':{
    'constraints':[
      { "min_version" : "2.1.0", "fixed_version" : "2.1.4" }
    ],
    'instances':make_list()
  },
  'System.IO.Pipelines':{
    'constraints':[
      { "min_version" : "4.5.0", "fixed_version" : "4.6.26814.2" },
    ],
    'instances':make_list()
  }
};

port = kb_smb_transport();

# Only need one install - packages for all installs will be enumerated
install = get_single_install(app_name:appname);
version = install['version'];
path = install['path'];
# Parse extras
foreach package (keys(package_dat))
{
  foreach instance (split(install[package], sep:';', keep:false))
  {
    next = max_index(package_dat[package]['instances']);
    package_dat[package]['instances'][next] = split(instance, sep:'?', keep:false);
  }
}

report =
  '\n  Path              : ' + path +
  '\n  Installed version : ' + version +
  '\n';

vuln = false;
foreach package (keys(package_dat))
{
  foreach instance (package_dat[package]['instances'])
  {
    out = vcf::check_version(
      version:vcf::parse_version(instance[0]),
      constraints:package_dat[package]['constraints']
    );
    if (!vcf::is_error(out) && !isnull(out))
    {
      vuln = true;
      report +=
        '\n  Package           : ' + package +
        '\n  Path              : ' + instance[1] +
        '\n  Installed version : ' + instance[0] +
        '\n  Fixed version     : ' + out['fixed_version'] +
        '\n';
    }
  }
}

if (vuln)
  security_report_v4(port:port, severity:SECURITY_WARNING, extra:report);
else
  audit(AUDIT_INST_VER_NOT_VULN, appname);