NetScaler ADC and NetScaler Gateway Memory Overflow (CTX697191 / CVE-2026-107406)

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

include('compat.inc');

if (description)
{
  script_id(366457);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/19");

  script_cve_id("CVE-2026-107406");
  script_xref(name:"IAVA", value:"2026-A-1120");

  script_name(english:"NetScaler ADC and NetScaler Gateway Memory Overflow (CTX697191 / CVE-2026-107406)");

  script_set_attribute(attribute:"synopsis", value:
"The remote device is affected by a memory overflow vulnerability.");
  script_set_attribute(attribute:"description", value:
"The remote NetScaler ADC (formerly Citrix ADC) or NetScaler Gateway (formerly Citrix Gateway) device is
13.1 prior to 13.1-64.29, or 14.1 prior or equal to 14.1-73.41, or 13.1-FIPS/NDcPP prior to 13.1-37.283, or
14.1-FIPS prior or equal to 14.1-73.41 FIPS. It is, therefore, affected by a vulnerability:

  - Memory overflow vulnerability in NetScaler ADC and NetScaler Gateway leading to Remote Code Execution or
    Denial of Service. The appliance must be configured as a SAML SP or SAML IdP to be affected. Versions
    13.1-64.23 through 13.1-64.28, 14.1-73.37 through 14.1-73.41, 13.1-NDcPP 13.1-37.279 through 13.1-37.282,
    and 14.1-73.37 FIPS through 14.1-73.41 FIPS are affected only when configured as a SAML IdP.
    (CVE-2026-107406)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported
version number.");
  # https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX697191
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?11ad6f94");
  script_set_attribute(attribute:"solution", value:
"Upgrade to NetScaler ADC or NetScaler Gateway version 13.1-64.29, 14.1-73.46, 13.1-37.283-FIPS,
13.1-37.283-NDcPP, or 14.1-73.46-FIPS or later.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss4_vector", value:"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:L");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-107406");

  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:"2026/10/08");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/10/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/16");

  script_set_attribute(attribute:"plugin_type", value:"combined");
  script_set_attribute(attribute:"cpe", value:"cpe:/h:citrix:netscaler_gateway");
  script_set_attribute(attribute:"cpe", value:"cpe:/h:citrix:netscaler_application_delivery_controller");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"CGI abuses");

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

  script_dependencies("citrix_netscaler_detect.nbin");
  script_require_keys("Host/NetScaler/Detected");

  exit(0);
}

include('vcf_extras_netscaler.inc');

var app_info = vcf::citrix_netscaler::get_app_info();

# The appliance must be configured as a SAML SP or SAML IdP, which cannot be verified.
if (report_paranoia < 2) audit(AUDIT_POTENTIAL_VULN, 'Citrix NetScaler', app_info.display_version);

var constraints;

# 14.1 / 14.1-FIPS: the last version documented as affected is 14.1-73.41; the vendor fix is 14.1-73.46.
if (app_info['fips_status'] == 1)
  constraints = [
    {'fips':TRUE, 'min_version': '13.1', 'fixed_version': '13.1.37.283', 'fixed_display':'13.1-37.283-FIPS/NDcPP'},
    {'fips':TRUE, 'min_version': '14.1', 'max_version': '14.1.73.41', 'fixed_display':'14.1-73.46-FIPS'}
  ];
else
  constraints = [
    {'min_version': '13.1', 'fixed_version': '13.1.64.29', 'fixed_display': '13.1-64.29'},
    {'min_version': '14.1', 'max_version': '14.1.73.41', 'fixed_display': '14.1-73.46'}
  ];

vcf::citrix_netscaler::check_version_and_report(
  app_info:app_info,
  constraints:constraints,
  severity:SECURITY_HOLE
);