Microsoft Exchange Server Elevation of Privilege (October 2026)

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

include('compat.inc');

if (description)
{
  script_id(363863);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/07");

  script_cve_id("CVE-2026-96940");
  script_xref(name:"MSKB", value:"5129955");
  script_xref(name:"MSKB", value:"5129956");
  script_xref(name:"MSKB", value:"5129957");
  script_xref(name:"MSKB", value:"5129958");
  script_xref(name:"MSFT", value:"MS26-5129955");
  script_xref(name:"MSFT", value:"MS26-5129956");
  script_xref(name:"MSFT", value:"MS26-5129957");
  script_xref(name:"MSFT", value:"MS26-5129958");

  script_name(english:"Microsoft Exchange Server Elevation of Privilege (October 2026)");

  script_set_attribute(attribute:"synopsis", value:
"The Microsoft Exchange Server installed on the remote host is affected by an elevation of privilege
vulnerability.");
  script_set_attribute(attribute:"description", value:
"The Microsoft Exchange Server installed on the remote host is missing a security update. It is,
therefore, affected by an elevation of privilege vulnerability. Weak authorization in Microsoft
Exchange Server allows an authenticated attacker to elevate privileges over a network.
(CVE-2026-96940)

Note that Nessus has not tested for this issue but has instead relied only on the application's
self-reported version number.");
  # https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-96940
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?d6563688");
  script_set_attribute(attribute:"see_also", value:"https://support.microsoft.com/help/5129955");
  script_set_attribute(attribute:"see_also", value:"https://support.microsoft.com/help/5129956");
  script_set_attribute(attribute:"see_also", value:"https://support.microsoft.com/help/5129957");
  script_set_attribute(attribute:"see_also", value:"https://support.microsoft.com/help/5129958");
  script_set_attribute(attribute:"solution", value:
"Microsoft has released a security update for Microsoft Exchange Server. Apply the applicable
Security Update for your Exchange Server version.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-96940");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/10/02");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/10/02");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/07");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:microsoft:exchange_server:2016");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:microsoft:exchange_server:2019");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:microsoft:exchange_server:subscription_edition");
  script_end_attributes();

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

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

  script_dependencies("ms_bulletin_checks_possible.nasl", "microsoft_exchange_installed.nbin");
  script_require_keys("SMB/MS_Bulletin_Checks/Possible");
  script_require_ports(139, 445, "Host/patch_management_checks");

  exit(0);
}

include('vcf.inc');
include('vcf_extras_microsoft.inc');

var app_info = vcf::microsoft::exchange::get_app_info();

var constraints = [
  { 'fixed_version' : '15.1.2507.75', 'product' : '2016', 'cu' : 23, 'unsupported_cu' : 22, 'kb' : '5129958' },
  { 'fixed_version' : '15.2.1544.48', 'product' : '2019', 'cu' : 14, 'unsupported_cu' : 13, 'kb' : '5129957' },
  { 'fixed_version' : '15.2.1748.53', 'product' : '2019', 'cu' : 15, 'unsupported_cu' : 13, 'kb' : '5129956' },
  { 'fixed_version' : '15.2.2562.53', 'product' : 'Subscription Edition', 'cu' : 0, 'kb' : '5129955' }
];

vcf::microsoft::exchange::check_version_and_report(
  app_info:app_info,
  bulletin:'MS26-10',
  constraints:constraints,
  severity:SECURITY_HOLE
);