Devolutions Server 2026.2.4.0 <= 2026.2.9.0 MFA Bypass (DEVO-2026-0023)

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

include('compat.inc');

if (description)
{
  script_id(326247);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/07/13");

  script_cve_id("CVE-2026-14536");
  script_xref(name:"IAVB", value:"2026-B-0189");

  script_name(english:"Devolutions Server 2026.2.4.0 <= 2026.2.9.0 MFA Bypass (DEVO-2026-0023)");

  script_set_attribute(attribute:"synopsis", value:
"The Devolutions Server instance installed on the remote host is affected by an authentication bypass vulnerability.");
  script_set_attribute(attribute:"description", value:
"The version of Devolutions Server installed on the remote host is 2026.2.4.0 prior or equal to 2026.2.9.0 and is, therefore,
affected by an authentication bypass vulnerability:

  - Improper enforcement of a mandatory multi-factor authentication policy in Devolutions Server 2026.2.9.0 allows an
    attacker with valid user credentials to bypass the MFA Required policy and authenticate without completing
    multi-factor authentication. The problem occurs when DVLS encounters an invalid default MFA value.
    (CVE-2026-14536)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://devolutions.net/security/advisories/DEVO-2026-0023/");
  script_set_attribute(attribute:"solution", value:
"Upgrade to Devolutions Server version 2026.2.11.0 or later.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:C");
  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:L/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:"cvss_score_source", value:"CVE-2026-14536");

  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:"2026/07/06");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/07/06");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/07/10");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:devolutions:devolutions_server");
  script_set_attribute(attribute:"stig_severity", value:"I");
  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("devolutions_server_win_installed.nbin");
  script_require_keys("installed_sw/Devolutions Server");

  exit(0);
}

include('vdf.inc');

# @tvdl-content
var vuln_data = {
  'metadata': {'spec_version': '1.0'},
  'requires': [
    {'scope': 'target', 'match': {'os': 'windows'}}
  ],
  'checks': [
    {
      'product': {'name': 'Devolutions Server', 'type': 'app'},
      'check_algorithm': 'default',
      'constraints' : [
        { 'min_version': '2026.2.4.0', 'max_version': '2026.2.9.0', 'fixed_version':'2026.2.11.0' }
      ]
    }
  ]
};

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