Security Updates for Microsoft Exchange Server (July 2026)

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

include('compat.inc');

if (description)
{
  script_id(326858);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/07/17");

  script_cve_id(
    "CVE-2026-54998",
    "CVE-2026-55005",
    "CVE-2026-55006",
    "CVE-2026-55008",
    "CVE-2026-55009"
  );
  script_xref(name:"MSFT", value:"MS26-5103212");
  script_xref(name:"MSFT", value:"MS26-5103213");
  script_xref(name:"MSFT", value:"MS26-5103214");
  script_xref(name:"MSFT", value:"MS26-5103215");
  script_xref(name:"MSKB", value:"5103212");
  script_xref(name:"MSKB", value:"5103213");
  script_xref(name:"MSKB", value:"5103214");
  script_xref(name:"MSKB", value:"5103215");
  script_xref(name:"IAVA", value:"2026-A-0728");

  script_name(english:"Security Updates for Microsoft Exchange Server (July 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 a security update. It is, therefore, affected by
multiple vulnerabilities as referenced in the July, 2026 security bulletin.

  - Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange
    Server allows an unauthorized attacker to perform spoofing over a network. (CVE-2026-55008)

  - Incorrect authorization in Microsoft Exchange Online allows an authorized attacker to elevate privileges
    over a network. (CVE-2026-54998)

  - Heap-based buffer overflow in Microsoft Exchange Server allows an authorized attacker to execute code over
    a network. (CVE-2026-55005)

  - Insufficient granularity of access control in Microsoft Exchange Server allows an authorized attacker to
    elevate privileges locally. (CVE-2026-55006)

  - Deserialization of untrusted data in Microsoft Exchange Server allows an authorized attacker to elevate
    privileges locally. (CVE-2026-55009)

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:"solution", value:
"Microsoft has released the following security updates to address this issue:
  -KB5103213
  -KB5103214
  -KB5103215");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-55008");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/07/02");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/07/14");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/07/14");

  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:"stig_severity", value:"I");
  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' : '15.1.2507.71', 'product' : '2016', 'cu' : 23, 'unsupported_cu' : 22, 'kb' : '5103215' },
  { 'fixed_version' : '15.2.1544.43', 'product' : '2019', 'cu' : 14, 'unsupported_cu' : 13, 'kb' : '5103214' },
  { 'fixed_version' : '15.2.1748.48', 'product' : '2019', 'cu' : 15, 'unsupported_cu' : 13, 'kb' : '5103213' }
];

vcf::microsoft::exchange::check_version_and_report(
  app_info:app_info,
  bulletin:'MS26-07',
  constraints:constraints,
  severity:SECURITY_HOLE
);