KB5083768: Windows 11 Version 26H1 Security Update (April 2026)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, 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(306439);
  script_version("1.6");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/28");

  script_cve_id(
    "CVE-2026-20806",
    "CVE-2026-20928",
    "CVE-2026-23670",
    "CVE-2026-25184",
    "CVE-2026-25250",
    "CVE-2026-26151",
    "CVE-2026-26152",
    "CVE-2026-26153",
    "CVE-2026-26155",
    "CVE-2026-26156",
    "CVE-2026-26159",
    "CVE-2026-26160",
    "CVE-2026-26161",
    "CVE-2026-26162",
    "CVE-2026-26163",
    "CVE-2026-26165",
    "CVE-2026-26166",
    "CVE-2026-26167",
    "CVE-2026-26168",
    "CVE-2026-26169",
    "CVE-2026-26170",
    "CVE-2026-26172",
    "CVE-2026-26173",
    "CVE-2026-26174",
    "CVE-2026-26175",
    "CVE-2026-26176",
    "CVE-2026-26177",
    "CVE-2026-26179",
    "CVE-2026-26180",
    "CVE-2026-26181",
    "CVE-2026-26182",
    "CVE-2026-26184",
    "CVE-2026-27906",
    "CVE-2026-27907",
    "CVE-2026-27908",
    "CVE-2026-27909",
    "CVE-2026-27910",
    "CVE-2026-27911",
    "CVE-2026-27914",
    "CVE-2026-27915",
    "CVE-2026-27916",
    "CVE-2026-27917",
    "CVE-2026-27918",
    "CVE-2026-27919",
    "CVE-2026-27920",
    "CVE-2026-27921",
    "CVE-2026-27922",
    "CVE-2026-27923",
    "CVE-2026-27925",
    "CVE-2026-27926",
    "CVE-2026-27927",
    "CVE-2026-27929",
    "CVE-2026-27930",
    "CVE-2026-27931",
    "CVE-2026-32068",
    "CVE-2026-32069",
    "CVE-2026-32070",
    "CVE-2026-32071",
    "CVE-2026-32072",
    "CVE-2026-32073",
    "CVE-2026-32074",
    "CVE-2026-32075",
    "CVE-2026-32076",
    "CVE-2026-32077",
    "CVE-2026-32078",
    "CVE-2026-32079",
    "CVE-2026-32081",
    "CVE-2026-32082",
    "CVE-2026-32083",
    "CVE-2026-32084",
    "CVE-2026-32085",
    "CVE-2026-32086",
    "CVE-2026-32087",
    "CVE-2026-32088",
    "CVE-2026-32089",
    "CVE-2026-32090",
    "CVE-2026-32091",
    "CVE-2026-32093",
    "CVE-2026-32149",
    "CVE-2026-32150",
    "CVE-2026-32151",
    "CVE-2026-32152",
    "CVE-2026-32153",
    "CVE-2026-32154",
    "CVE-2026-32156",
    "CVE-2026-32157",
    "CVE-2026-32158",
    "CVE-2026-32159",
    "CVE-2026-32160",
    "CVE-2026-32162",
    "CVE-2026-32163",
    "CVE-2026-32164",
    "CVE-2026-32165",
    "CVE-2026-32181",
    "CVE-2026-32183",
    "CVE-2026-32195",
    "CVE-2026-32202",
    "CVE-2026-32212",
    "CVE-2026-32214",
    "CVE-2026-32215",
    "CVE-2026-32216",
    "CVE-2026-32217",
    "CVE-2026-32218",
    "CVE-2026-32219",
    "CVE-2026-32220",
    "CVE-2026-32221",
    "CVE-2026-32222",
    "CVE-2026-32223",
    "CVE-2026-32224",
    "CVE-2026-32225",
    "CVE-2026-33096",
    "CVE-2026-33098",
    "CVE-2026-33100",
    "CVE-2026-33101",
    "CVE-2026-33104",
    "CVE-2026-33824",
    "CVE-2026-33827",
    "CVE-2026-33829"
  );
  script_xref(name:"MSKB", value:"5083768");
  script_xref(name:"MSFT", value:"MS26-5083768");
  script_xref(name:"IAVA", value:"2026-A-0342");
  script_xref(name:"IAVA", value:"2026-A-0343");
  script_xref(name:"CISA-KNOWN-EXPLOITED", value:"2026/05/12");

  script_name(english:"KB5083768: Windows 11 Version 26H1 Security Update (April 2026)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Windows host is affected by multiple vulnerabilities.");
  script_set_attribute(attribute:"description", value:
"The remote Windows host is missing security update 5083768. It is, therefore, affected by multiple vulnerabilities

  - Double free in Windows IKE Extension allows an unauthorized attacker to execute code over a network.
    (CVE-2026-33824)

  - Protection mechanism failure in Windows Shell allows an unauthorized attacker to bypass a security feature
    over a network. (CVE-2026-32225)

  - Use after free in Remote Desktop Client allows an unauthorized attacker to execute code over a network.
    (CVE-2026-32157)

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/5083768");
  script_set_attribute(attribute:"solution", value:
"Apply Security Update 5083768");
  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:F/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:F/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-33824");
  script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2026-26167");

  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:"2026/04/14");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/04/14");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/04/14");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:microsoft:windows_11_26h1");
  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("smb_check_rollup.nasl", "smb_hotfixes.nasl", "ms_bulletin_checks_possible.nasl");
  script_require_keys("SMB/MS_Bulletin_Checks/Possible");
  script_require_ports(139, 445, "Host/patch_management_checks");

  exit(0);
}

include('smb_func.inc');
include('smb_hotfixes.inc');
include('smb_hotfixes_fcheck.inc');
include('smb_reg_query.inc');

get_kb_item_or_exit('SMB/MS_Bulletin_Checks/Possible');

var bulletin = 'MS26-04';
var kbs = make_list(
  '5083768'
);

if (get_kb_item('Host/patch_management_checks')) hotfix_check_3rd_party(bulletin:bulletin, kbs:kbs, severity:SECURITY_HOLE);

get_kb_item_or_exit('SMB/Registry/Enumerated');
get_kb_item_or_exit('SMB/WindowsVersion', exit_code:1);

if (hotfix_check_sp_range(win10:'0') <= 0) audit(AUDIT_OS_SP_NOT_VULN);

var share = hotfix_get_systemdrive(as_share:TRUE, exit_on_fail:TRUE);
if (!is_accessible_share(share:share)) audit(AUDIT_SHARE_FAIL, share);

if (
  smb_check_rollup(os:'10',
                   os_build:28000,
                   rollup_date:'04_2026',
                   bulletin:bulletin,
                   rollup_kb_list:[5083768])
)
{
  replace_kb_item(name:'SMB/Missing/'+bulletin, value:TRUE);
  hotfix_security_hole();
  hotfix_check_fversion_end();
  exit(0);
}
else
{
  hotfix_check_fversion_end();
  audit(AUDIT_HOST_NOT, hotfix_get_audit_report());
}