ISC BIND Buffer Overflow Vulnerability (CVE-2020-8625) - Windows

# Copyright (C) 2021 Greenbone Networks GmbH
# Some text descriptions might be excerpted from (a) referenced
# source(s), and are Copyright (C) by the respective right holder(s).
#
# SPDX-License-Identifier: GPL-2.0-or-later
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

CPE = "cpe:/a:isc:bind";

if (description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.145413");
  script_version("2021-08-17T14:01:00+0000");
  script_tag(name:"last_modification", value:"2021-08-17 14:01:00 +0000 (Tue, 17 Aug 2021)");
  script_tag(name:"creation_date", value:"2021-02-18 04:01:18 +0000 (Thu, 18 Feb 2021)");
  script_tag(name:"cvss_base", value:"6.8");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:M/Au:N/C:P/I:P/A:P");
  script_tag(name:"severity_vector", value:"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H");
  script_tag(name:"severity_origin", value:"NVD");
  script_tag(name:"severity_date", value:"2021-03-19 22:15:00 +0000 (Fri, 19 Mar 2021)");

  script_cve_id("CVE-2020-8625");

  script_tag(name:"qod_type", value:"remote_banner");

  script_tag(name:"solution_type", value:"VendorFix");

  script_name("ISC BIND Buffer Overflow Vulnerability (CVE-2020-8625) - Windows");

  script_category(ACT_GATHER_INFO);

  script_copyright("Copyright (C) 2021 Greenbone Networks GmbH");
  script_family("Buffer overflow");
  script_dependencies("gb_isc_bind_consolidation.nasl", "os_detection.nasl");
  script_mandatory_keys("isc/bind/detected", "Host/runs_windows");

  script_tag(name:"summary", value:"ISC BIND is prone to a buffer overflow vulnerability in the GSSAPI security
  policy negotiation.");

  script_tag(name:"vuldetect", value:"Checks if a vulnerable version is present on the target host.");

  script_tag(name:"insight", value:"GSS-TSIG is an extension to the TSIG protocol which is intended to support
  the secure exchange of keys for use in verifying the authenticity of communications between parties on a
  network.

  SPNEGO is a negotiation mechanism used by GSSAPI, the application protocol interface for GSS-TSIG.

  The SPNEGO implementation used by BIND has been found to be vulnerable to a buffer overflow attack.");

  script_tag(name:"impact", value:"The most likely outcome of a successful exploitation of the vulnerability
  is a crash of the named process. However, remote code execution, while unproven, is theoretically possible.");

  script_tag(name:"affected", value:"BIND 9.5.0 - 9.11.27, 9.12.0 - 9.16.11, 9.11.3-S1 - 9.11.27-S1 and
  9.16.8-S1 - 9.16.11-S1.");

  script_tag(name:"solution", value:"Update to version 9.11.28, 9.16.12, 9.11.28-S1, 9.16.12-S1 or later.");

  script_xref(name:"URL", value:"https://kb.isc.org/docs/cve-2020-8625");

  exit(0);
}

include("host_details.inc");
include("version_func.inc");

if (isnull(port = get_app_port(cpe: CPE)))
  exit(0);

if (!infos = get_app_full(cpe: CPE, port: port, exit_no_version: TRUE))
  exit(0);

version = infos["version"];
proto = infos["proto"];
location = infos["location"];

if (version =~ "^9\.(11|16)\.[0-9]+s[0-9]") {
  if (version_in_range(version: version, test_version: "9.11.3s1", test_version2: "9.11.27s1")) {
    report = report_fixed_ver(installed_version: version, fixed_version: "9.11.28-S1", install_path: location);
    security_message(port: port, data: report, proto: proto);
    exit(0);
  }

  if (version_in_range(version: version, test_version: "9.16.8s1", test_version2: "9.16.11s1")) {
    report = report_fixed_ver(installed_version: version, fixed_version: "9.16.12-S1", install_path: location);
    security_message(port: port, data: report, proto: proto);
    exit(0);
  }
} else {
  if (version_in_range(version: version, test_version: "9.5.0", test_version2: "9.11.27")) {
    report = report_fixed_ver(installed_version: version, fixed_version: "9.11.28", install_path: location);
    security_message(port: port, data: report, proto: proto);
    exit(0);
  }

  if (version_in_range(version: version, test_version: "9.12.0", test_version2: "9.16.11")) {
    report = report_fixed_ver(installed_version: version, fixed_version: "9.16.12", install_path: location);
    security_message(port: port, data: report, proto: proto);
    exit(0);
  }
}

exit(99);