Citrix Workspace App for Windows Out-of-bounds Read and Write (CVE-2026-84420) (CTX697181)

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

include('compat.inc');

if (description)
{
  script_id(370486);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/23");

  script_cve_id("CVE-2026-84420");

  script_name(english:"Citrix Workspace App for Windows Out-of-bounds Read and Write (CVE-2026-84420) (CTX697181)");

  script_set_attribute(attribute:"synopsis", value:
"The remote host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"The version of Citrix Workspace App for Windows installed on the remote host is 2507.1 LTSR prior to 2507.1 LTSR CU3,
or Current Release prior to 2603.20. It is, therefore, affected by an out-of-bounds read and out-of-bounds write
vulnerability as referenced in the CTX697181 advisory.

  - Out-of-bounds read vulnerability in Citrix Workspace app for Windows. This issue affects Citrix Workspace
    app for Windows: before 2603.20 CR, before LTSR 2607, and before LTSR 2507 CU3. (CVE-2026-84420)

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=CTX697181
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?e4e9a075");
  script_set_attribute(attribute:"solution", value:
"Upgrade to Citrix Workspace App for Windows 2603.20 CR, 2507.1 LTSR CU3, 2607 LTSR or later.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:H/Au:S/C:P/I:P/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/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:L/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-84420");
  script_set_attribute(attribute:"cvss_score_rationale", value:"Score based on analysis of the vendor advisory.");
  script_set_attribute(attribute:"cvss3_score_rationale", value:"Score based on analysis of the vendor advisory.");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");
  script_cwe_id(125, 787);

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/10/13");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/10/13");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/22");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:citrix:workspace");
  script_end_attributes();

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

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

  script_dependencies("citrix_workspace_win_installed.nbin");
  script_require_keys("installed_sw/Citrix Workspace", "SMB/Registry/Enumerated");

  exit(0);
}

include('vdf.inc');

# @tvdl-content
var vuln_data = {
  'metadata': {'spec_version': '1.0'},
  'requires': [
    {'scope': 'target', 'match': {'os': 'windows'}}
  ],
  'checks': [
    {
      'product': {'name': 'Citrix Workspace', 'type': 'app'},
      'check_algorithm': 'default',
      'constraints': [
        { 'min_version' : '25.7.0.0', 'fixed_version' : '25.7.3000', 'fixed_display' : '2507.1 LTSR CU3 or 2607 LTSR' },
        { 'min_version' : '25.8.0.0', 'fixed_version' : '26.3.20', 'fixed_display' : '2603.20 CR or 2607 LTSR' }
      ]
    }
  ]
};

var vdf_result = vdf::check_and_report(vuln_data:vuln_data, severity:SECURITY_WARNING);
vdf::handle_check_and_report_errors(vdf_result:vdf_result);