OpenLDAP DoS Vulnerability (Feb 2021)

# 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,
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
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# 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:openldap:openldap";

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.146990");
  script_version("2021-10-27T14:04:00+0000");
  script_tag(name:"last_modification", value:"2021-10-27 14:04:00 +0000 (Wed, 27 Oct 2021)");
  script_tag(name:"creation_date", value:"2021-10-27 08:01:39 +0000 (Wed, 27 Oct 2021)");
  script_tag(name:"cvss_base", value:"5.0");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:L/Au:N/C:N/I:N/A:P");
  script_tag(name:"severity_vector", value:"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H");
  script_tag(name:"severity_origin", value:"NVD");
  script_tag(name:"severity_date", value:"2021-06-29 15:15:00 +0000 (Tue, 29 Jun 2021)");

  script_cve_id("CVE-2021-27212");

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

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

  script_name("OpenLDAP DoS Vulnerability (Feb 2021)");

  script_category(ACT_GATHER_INFO);
  script_copyright("Copyright (C) 2021 Greenbone Networks GmbH");
  script_family("Denial of Service");
  script_dependencies("gb_openldap_consolidation.nasl");
  script_mandatory_keys("openldap/detected");

  script_tag(name:"summary", value:"OpenLDAP is prone to a denial of service (DoS) vulnerability.");

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

  script_tag(name:"insight", value:"In OpenLDAP an assertion failure in slapd can occur in the
  issuerAndThisUpdateCheck function via a crafted packet, resulting in a denial of service (daemon
  exit) via a short timestamp. This is related to schema_init.c and checkTime.");

  script_tag(name:"affected", value:"OpenLDAP version 2.4.57 and prior and 2.5.x through 2.5.1alpha.");

  script_tag(name:"solution", value:"Update to version 2.4.58, 2.5.4 or later.");

  script_xref(name:"URL", value:"https://bugs.openldap.org/show_bug.cgi?id=9454");

  exit(0);
}

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

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

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

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

if (version_is_less(version: version, test_version: "2.4.58")) {
  report = report_fixed_ver(installed_version: version, fixed_version: "2.4.58", install_path: location);
  security_message(port: port, data: report);
  exit(0);
}

if (version =~ "^2\.5" && version_is_less(version: version, test_version: "2.5.4")) {
  report = report_fixed_ver(installed_version: version, fixed_version: "2.5.4", install_path: location);
  security_message(port: port, data: report);
  exit(0);
}

exit(99);