This host is installed with openssh and
is prone to denial of service and user enumeration vulnerabilities.
###############################################################################
# OpenVAS Vulnerability Test
#
# OpenSSH Denial of Service And User Enumeration Vulnerabilities (Windows)
#
# Authors:
# Tushar Khelge <[email protected]>
#
# Copyright:
# Copyright (C) 2016 Greenbone Networks GmbH, http://www.greenbone.net
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2
# (or any later version), as published by the Free Software Foundation.
#
# 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:openbsd:openssh";
if(description)
{
script_oid("1.3.6.1.4.1.25623.1.0.809121");
script_version("2019-05-21T12:48:06+0000");
script_cve_id("CVE-2016-6515", "CVE-2016-6210");
script_bugtraq_id(92212);
script_tag(name:"cvss_base", value:"7.8");
script_tag(name:"cvss_base_vector", value:"AV:N/AC:L/Au:N/C:N/I:N/A:C");
script_tag(name:"last_modification", value:"2019-05-21 12:48:06 +0000 (Tue, 21 May 2019)");
script_tag(name:"creation_date", value:"2016-08-18 10:29:27 +0530 (Thu, 18 Aug 2016)");
script_name("OpenSSH Denial of Service And User Enumeration Vulnerabilities (Windows)");
script_copyright("Copyright (C) 2016 Greenbone Networks GmbH");
script_category(ACT_GATHER_INFO);
script_family("Denial of Service");
script_dependencies("gb_openssh_consolidation.nasl", "os_detection.nasl");
script_mandatory_keys("openssh/detected", "Host/runs_windows");
script_xref(name:"URL", value:"http://www.openssh.com/txt/release-7.3");
script_xref(name:"URL", value:"http://seclists.org/fulldisclosure/2016/Jul/51");
script_xref(name:"URL", value:"https://security-tracker.debian.org/tracker/CVE-2016-6210");
script_xref(name:"URL", value:"http://openwall.com/lists/oss-security/2016/08/01/2");
script_tag(name:"summary", value:"This host is installed with openssh and
is prone to denial of service and user enumeration vulnerabilities.");
script_tag(name:"vuldetect", value:"Checks if a vulnerable version is present on the target host.");
script_tag(name:"insight", value:"Multiple flaws exist due to,
- The auth_password function in 'auth-passwd.c' script does not limit password
lengths for password authentication.
- The sshd in OpenSSH, when SHA256 or SHA512 are used for user password hashing
uses BLOWFISH hashing on a static password when the username does not exist
and it takes much longer to calculate SHA256/SHA512 hash than BLOWFISH hash.");
script_tag(name:"impact", value:"Successfully exploiting this issue allows
remote attackers to cause a denial of service (crypt CPU consumption) and
to enumerate users by leveraging the timing difference between responses
when a large password is provided.");
script_tag(name:"affected", value:"OpenSSH versions before 7.3 on Windows");
script_tag(name:"solution", value:"Upgrade to OpenSSH version 7.3 or later.");
script_tag(name:"solution_type", value:"VendorFix");
script_tag(name:"qod_type", value:"remote_banner");
exit(0);
}
include("version_func.inc");
include("host_details.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);
vers = infos["version"];
path = infos["location"];
if(version_is_less(version:vers, test_version:"7.3")) {
report = report_fixed_ver(installed_version:vers, fixed_version:"7.3", install_path:path);
security_message(port:port, data:report);
exit(0);
}
exit(99);