Knot DNS 1.5.2 Incremental Zone Transfer (IXFR) DoS

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

include("compat.inc");

if (description)
{
  script_id(78890);
  script_version("1.4");
  script_cvs_date("Date: 2019/11/26");

  script_cve_id("CVE-2014-0486");
  script_bugtraq_id(70097);

  script_name(english:"Knot DNS 1.5.2 Incremental Zone Transfer (IXFR) DoS");
  script_summary(english:"Checks the version of Knot DNS.");

  script_set_attribute(attribute:"synopsis", value:
"The remote DNS server is potentially affected by a denial of service
vulnerability.");
  script_set_attribute(attribute:"description", value:
"The remote host is running Knot DNS version 1.5.2. It is, therefore,
affected by an error that could allow certain Incremental Zone
Transfer (IXFR) messages to crash the server.");
  script_set_attribute(attribute:"see_also", value:"https://lists.nic.cz/pipermail/knot-dns-users/2014-September/000507.html");
  script_set_attribute(attribute:"see_also", value:"https://gitlab.labs.nic.cz/labs/knot/issues/294");
  # https://gitlab.labs.nic.cz/labs/knot/commit/7c7236c24cce8f7c3a094163bf3c31858f68e8ca
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?94f30f0a");
  script_set_attribute(attribute:"solution", value:
"Update to version 1.5.3 or later.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/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-2014-0486");

  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:"2014/09/15");
  script_set_attribute(attribute:"patch_publication_date", value:"2014/09/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2014/11/06");

  script_set_attribute(attribute:"potential_vulnerability", value:"true");
  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"x-cpe:/a:cz.nic:knot_dns");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2014-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("knot_dns_version.nasl");
  script_require_keys("knot_dns/proto", "Settings/ParanoidReport");

  exit(0);
}

include("audit.inc");
include("global_settings.inc");
include("misc_func.inc");

# May fork
proto = get_kb_item("knot_dns/proto");

port = 53;
version = get_kb_item_or_exit("knot_dns/"+proto+"/version");
num_ver = get_kb_item_or_exit("knot_dns/"+proto+"/num_ver");

if (version =~ "^1(\.5)?$") audit(AUDIT_VER_NOT_GRANULAR, "Knot DNS", port, version);

if (report_paranoia < 2) audit(AUDIT_PARANOID);

fix = "1.5.3";

if (
  version =~ "^1\.5\.2($|[^0-9])" ||
  version =~ "^1\.5\.3-rc\d+"
)
{
  if (report_verbosity > 0)
  {
    report =
      '\n  Installed version : ' + version +
      '\n  Fixed version     : ' + fix +
      '\n';
    security_warning(port:port, proto:tolower(proto), extra:report);
  }
  else security_warning(port:port, proto:tolower(proto));
}
else audit(AUDIT_LISTEN_NOT_VULN, "Knot DNS", port, version, proto);