Tenda AC Router Stack Buffer Overflow (CVE-2021-31755)

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

include('compat.inc');

if (description)
{
  script_id(186359);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/11/29");

  script_cve_id("CVE-2021-31755");
  script_xref(name:"CISA-KNOWN-EXPLOITED", value:"2021/11/17");

  script_name(english:"Tenda AC Router Stack Buffer Overflow (CVE-2021-31755)");

  script_set_attribute(attribute:"synopsis", value:
"The remote router is affected by a stack buffer overflow vulnerability.");
  script_set_attribute(attribute:"description", value:
"The firmware version of the Tenda AC Router is an AC11 device with firmware 02.03.01.104_CN or below. It is, therefore,
affected by a stack buffer overflow vulnerability. An unauthenticated, remote attacker can exploit this, via
a crafted POST request, to execute arbitrary code on the system.

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://nvd.nist.gov/vuln/detail/CVE-2021-31755");
  script_set_attribute(attribute:"solution", value:
"Update to a newer version of device firmware.");
  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:N/AC:L/PR:N/UI:N/S:U/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-2021-31755");

  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:"2021/05/07");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/05/07");
  script_set_attribute(attribute:"plugin_publication_date", value:"2023/11/28");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/h:tenda:ac11");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2023 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("tenda_ac_router_detect.nbin");
  script_require_keys("installed_sw/Tenda AC Router");

  exit(0);
}

include('vcf_extras_tenda.inc');

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

var constraints = [
  { 'model' : 'AC11', 'max_version' : '2.03.01.104',  'fixed_display' : 'Upgrade to a newer firmware' }
];

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