Fortinet FortiWeb - Weak generation of WAF session IDs leads to session fixation (FG-IR-21-214)

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

include('compat.inc');

if (description)
{
  script_id(197611);
  script_version("1.0");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/05/22");

  script_cve_id("CVE-2021-42761");

  script_name(english:"Fortinet FortiWeb - Weak generation of WAF session IDs leads to session fixation (FG-IR-21-214)");

  script_set_attribute(attribute:"synopsis", value:
"Fortinet Firewall is missing one or more security-related updates.");
  script_set_attribute(attribute:"description", value:
"The version of FortiWeb installed on the remote host is prior to tested version. It is, therefore, affected by a
vulnerability as referenced in the FG-IR-21-214 advisory.

  - A condition for session fixation vulnerability [CWE-384] in the session management of FortiWeb versions
    6.4 all versions, 6.3.0 through 6.3.16, 6.2.0 through 6.2.6, 6.1.0 through 6.1.2, 6.0.0 through 6.0.7,
    5.9.0 through 5.9.1 may allow a remote, unauthenticated attacker to infer the session identifier of other
    users and possibly usurp their session. (CVE-2021-42761)

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://www.fortiguard.com/psirt/FG-IR-21-214");
  script_set_attribute(attribute:"solution", value:
"Upgrade to FortiWeb version 5.9.2 / 6.0.8 / 6.1.3 / 6.2.7 / 6.3.17 / 7.0.0 or later.");
  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: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:"cvss_score_source", value:"CVE-2021-42761");

  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:"2023/02/16");
  script_set_attribute(attribute:"patch_publication_date", value:"2023/02/16");
  script_set_attribute(attribute:"plugin_publication_date", value:"2024/05/22");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:fortinet:fortiweb");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2024 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("fortinet_version.nbin");
  script_require_keys("Host/Fortigate/model", "Host/Fortigate/version");

  exit(0);
}

include('vcf_extras_fortios.inc');

var app_name = 'FortiWeb';
var app_info = vcf::get_app_info(app:app_name, kb_ver:'Host/Fortigate/version');
vcf::fortios::verify_product_and_model(product_name:app_name);

var constraints = [
  { 'min_version' : '5.6.0', 'max_version' : '5.6.2', 'fixed_version' : '5.9.2', 'fixed_display' : '5.9.2' },
  { 'min_version' : '5.7.0', 'max_version' : '5.7.3', 'fixed_version' : '5.9.2', 'fixed_display' : '5.9.2' },
  { 'min_version' : '5.8.0', 'max_version' : '5.8.7', 'fixed_version' : '5.9.2', 'fixed_display' : '5.9.2' },
  { 'min_version' : '5.9.0', 'fixed_version' : '5.9.2' },
  { 'min_version' : '6.0.0', 'fixed_version' : '6.0.8' },
  { 'min_version' : '6.1.0', 'fixed_version' : '6.1.3' },
  { 'min_version' : '6.2.0', 'fixed_version' : '6.2.7' },
  { 'min_version' : '6.3.0', 'fixed_version' : '6.3.17' },
  { 'min_version' : '6.4.0', 'max_version' : '6.4.2', 'fixed_version' : '7.0.0', 'fixed_display' : '7.0.0' }
];

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