ISC BIND 9.10.x < 9.11.22, 9.12.x < 9.16.6, 9.17.x < 9.17.4 DoS

#
# (C) Tenable Network Security, Inc.
#

include('compat.inc');

if (description)
{
  script_id(139917);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2021/06/03");

  script_cve_id("CVE-2020-8623");
  script_xref(name:"IAVA", value:"2020-A-0385-S");

  script_name(english:"ISC BIND 9.10.x < 9.11.22, 9.12.x < 9.16.6, 9.17.x < 9.17.4 DoS");

  script_set_attribute(attribute:"synopsis", value:
"The remote name server is affected by a denial of service vulnerability.");
  script_set_attribute(attribute:"description", value:
"According to its self-reported version number, the installation of ISC BIND running on the remote name server is 
version 9.10.x prior to 9.11.22, 9.12.x prior to 9.16.6 or 9.17.x prior to 9.17.4. It is, therefore, affected by a
denial of service (DoS). If BIND is built with --enable-native-pkcs11 then a specially crafted query for a zone signed
with RSA can trigger an assertion failure. An unauthenticated, remote attacker can exploit this issue via a specially
crafted query packet to trigger a crash on the server.

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://kb.isc.org/docs/cve-2020-8623");
  script_set_attribute(attribute:"solution", value:
"Upgrade to BIND 9.11.22, 9.16.6, 9.17.4 or later.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:N/I:N/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:N/I:N/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-2020-8623");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/08/20");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/08/20");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/08/27");

  script_set_attribute(attribute:"potential_vulnerability", value:"true");
  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:isc:bind");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2020-2021 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("bind_version.nasl");
  script_require_keys("bind/version", "Settings/ParanoidReport");

  exit(0);
}

include('vcf.inc');
include('vcf_extras.inc');

vcf::bind::initialize();
app_info = vcf::get_app_info(app:'BIND', port:53, kb_ver:'bind/version', service:TRUE, proto:'UDP');

# Must be running BIND that was built with "--enable-native-pkcs11"
if (report_paranoia < 2) audit(AUDIT_PARANOID);

constraints = [
  { 'min_version' : '9.10.0', 'fixed_version' : '9.11.0', 'fixed_display' : '9.11.22, 9.16.6, 9.17.4 or later' },
  { 'min_version' : '9.11.0', 'fixed_version' : '9.11.22' },
  { 'min_version' : '9.12.0', 'fixed_version' : '9.16.0', 'fixed_display' : '9.11.22, 9.16.6, 9.17.4 or later' },
  { 'min_version' : '9.16.0', 'fixed_version' : '9.16.6' },
  { 'min_version' : '9.17.0', 'fixed_version' : '9.17.4' }
];
constraints = vcf::bind::filter_constraints(constraints:constraints, version:app_info.version);

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