Security Update for Microsoft .NET Core (October 2025)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##

include('compat.inc');

if (description)
{
  script_id(270711);
  script_version("1.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/05/19");

  script_cve_id("CVE-2025-55248");
  script_xref(name:"IAVA", value:"2025-A-0752-S");

  script_name(english:"Security Update for Microsoft .NET Core (October 2025)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Windows host is affected by a .NET Core vulnerability");
  script_set_attribute(attribute:"description", value:
"The version of tested product installed on the remote host is prior to tested version. It is, therefore, affected by
information disclosure vulnerability as referenced in the vendor advisory.

  - Inadequate encryption strength in .NET, .NET Framework, Visual Studio allows an authorized attacker to 
    disclose information over a network. (CVE-2025-55248)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://dotnet.microsoft.com/en-us/download/dotnet/9.0");
  # https://github.com/dotnet/core/blob/master/release-notes/9.0/9.0.10/9.0.10.md
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?d39faa38");
  script_set_attribute(attribute:"see_also", value:"https://dotnet.microsoft.com/en-us/download/dotnet/8.0");
  # https://github.com/dotnet/core/blob/main/release-notes/8.0/8.0.21/8.0.21.md
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?22351646");
  script_set_attribute(attribute:"see_also", value:"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-55248");
  script_set_attribute(attribute:"see_also", value:"https://support.microsoft.com/help/5068332");
  script_set_attribute(attribute:"solution", value:
"Update .NET Core, remove vulnerable packages and refer to vendor advisory.");
  script_set_attribute(attribute:"agent", value:"all");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:H/Au:S/C:C/I:N/A:N");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:N/A:N");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2025-55248");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2025/10/14");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/10/14");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/10/17");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:microsoft:.net_core");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Misc.");

  script_copyright(english:"This script is Copyright (C) 2025-2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("microsoft_dotnet_core_win.nbin", "macosx_dotnet_core_installed.nbin");
  script_require_ports("installed_sw/.NET Core Windows", "installed_sw/.NET Core MacOS");

  exit(0);
}

include('vdf.inc');

# @tvdl-content
var vuln_data = {
  'metadata': {'spec_version': '1.0'},
  'checks': [
    {
      'product': {'name': '.NET Core Windows', 'type': 'app'},
      'check_algorithm': 'default',
      'requires': [{'scope': 'target', 'match': {'os': 'windows'}}],
      'constraints': [
        { 'min_version' : '8.0.0', 'fixed_version' : '8.0.21' },
        { 'min_version' : '9.0.0', 'fixed_version' : '9.0.10' }
      ]
    },
    {
      'product': {'name': '.NET Core MacOS', 'type': 'app'},
      'check_algorithm': 'default',
      'requires': [{'scope': 'target', 'match': {'os': 'macos'}}],
      'constraints': [
        { 'min_version' : '8.0.0', 'fixed_version' : '8.0.21' },
        { 'min_version' : '9.0.0', 'fixed_version' : '9.0.10' }
      ]
    }
  ]
};

var result = vdf::check_and_report(vuln_data:vuln_data, severity:SECURITY_WARNING);
vdf::handle_check_and_report_errors(vdf_result:result);