Security Updates for Microsoft Exchange Server (August 2026)

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

include('compat.inc');

if (description)
{
  script_id(334612);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/08/11");

  script_cve_id(
    "CVE-2026-62910",
    "CVE-2026-62911",
    "CVE-2026-62912",
    "CVE-2026-62913",
    "CVE-2026-62914",
    "CVE-2026-62915",
    "CVE-2026-65813"
  );
  script_xref(name:"MSKB", value:"5121573");
  script_xref(name:"MSKB", value:"5121574");
  script_xref(name:"MSKB", value:"5121575");
  script_xref(name:"MSKB", value:"5121576");
  script_xref(name:"MSFT", value:"MS26-5121573");
  script_xref(name:"MSFT", value:"MS26-5121574");
  script_xref(name:"MSFT", value:"MS26-5121575");
  script_xref(name:"MSFT", value:"MS26-5121576");

  script_name(english:"Security Updates for Microsoft Exchange Server (August 2026)");

  script_set_attribute(attribute:"synopsis", value:
"The Microsoft Exchange Server installed on the remote host is affected by multiple vulnerabilities.");
  script_set_attribute(attribute:"description", value:
"The Microsoft Exchange Server installed on the remote host is missing security updates. It is,
therefore, affected by multiple vulnerabilities:

  - Improper control of resource identifiers ('resource injection') in Microsoft Exchange Server allows an
    authorized attacker to elevate privileges over a network. (CVE-2026-62910)

  - Authentication bypass by capture-replay in Microsoft Exchange Server allows an authorized attacker to
    elevate privileges over a network. (CVE-2026-62911)

  - Heap-based buffer overflow in Microsoft Exchange Server allows an authorized attacker to execute code over
    a network. (CVE-2026-62913)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://support.microsoft.com/help/5121573");
  script_set_attribute(attribute:"see_also", value:"https://support.microsoft.com/help/5121574");
  script_set_attribute(attribute:"see_also", value:"https://support.microsoft.com/help/5121575");
  script_set_attribute(attribute:"see_also", value:"https://support.microsoft.com/help/5121576");
  script_set_attribute(attribute:"solution", value:
"Microsoft has released the following security updates to address this issue:
  -KB5121573
  -KB5121574
  -KB5121575
  -KB5121576");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:M/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-2026-62913");
  script_cwe_id(79, 99, 122, 294, 502, 862, 918);

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/08/11");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/08/11");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/08/11");

  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: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' : '15.1.2507.72', 'product' : '2016', 'cu' : 23, 'unsupported_cu' : 22, 'kb' : '5121576' },
  { 'fixed_version' : '15.2.1544.44', 'product' : '2019', 'cu' : 14, 'unsupported_cu' : 13, 'kb' : '5121575' },
  { 'fixed_version' : '15.2.1748.49', 'product' : '2019', 'cu' : 15, 'unsupported_cu' : 13, 'kb' : '5121574' },
  { 'fixed_version' : '15.2.2562.46', 'product' : 'Subscription Edition', 'cu' : 0, 'kb' : '5121573' }
];

vcf::microsoft::exchange::check_version_and_report(
  app_info:app_info,
  bulletin:'MS26-08',
  constraints:constraints,
  severity:SECURITY_HOLE
);