CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:M/Au:N/C:N/I:N/A:P
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
LOW
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:L
AI Score
Confidence
High
EPSS
Percentile
60.4%
A vulnerability in the TCP normalizer of Cisco Adaptive
Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to cause Cisco
ASA to drop any further incoming traffic on all interfaces, resulting in a denial of service
(DoS) condition.
# Copyright (C) 2017 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:cisco:asa";
if (description)
{
script_oid("1.3.6.1.4.1.25623.1.0.106767");
script_version("2022-02-24T08:32:00+0000");
script_tag(name:"last_modification", value:"2022-02-24 08:32:00 +0000 (Thu, 24 Feb 2022)");
script_tag(name:"creation_date", value:"2017-04-20 08:21:20 +0200 (Thu, 20 Apr 2017)");
script_tag(name:"cvss_base", value:"4.3");
script_tag(name:"cvss_base_vector", value:"AV:N/AC:M/Au:N/C:N/I:N/A:P");
script_tag(name:"severity_vector", value:"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:L");
script_tag(name:"severity_origin", value:"NVD");
script_tag(name:"severity_date", value:"2019-10-03 00:03:00 +0000 (Thu, 03 Oct 2019)");
script_cve_id("CVE-2017-3793");
script_tag(name:"qod_type", value:"remote_banner");
script_tag(name:"solution_type", value:"VendorFix");
script_name("Cisco ASA Software TCP Normalizer Denial of Service Vulnerability (cisco-sa-20170419-asa-norm)");
script_category(ACT_GATHER_INFO);
script_copyright("Copyright (C) 2017 Greenbone Networks GmbH");
script_family("CISCO");
script_dependencies("gb_cisco_asa_version.nasl", "gb_cisco_asa_version_snmp.nasl");
script_mandatory_keys("cisco_asa/version");
script_tag(name:"summary", value:"A vulnerability in the TCP normalizer of Cisco Adaptive
Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to cause Cisco
ASA to drop any further incoming traffic on all interfaces, resulting in a denial of service
(DoS) condition.");
script_tag(name:"vuldetect", value:"Checks if a vulnerable version is present on the target host.");
script_tag(name:"insight", value:"The vulnerability is due to improper limitation of the global
out-of-order TCP queue for specific block sizes. An attacker could exploit this vulnerability by
sending a large number of unique permitted TCP connections with out-of-order segments.");
script_tag(name:"impact", value:"An exploit could allow the attacker to exhaust available blocks
in the global out-of-order TCP queue, causing the dropping of any further incoming traffic on all
interfaces and resulting in a DoS condition.");
script_tag(name:"solution", value:"See the referenced vendor advisory for a solution.");
script_xref(name:"URL", value:"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170419-asa-norm");
exit(0);
}
include("host_details.inc");
include("version_func.inc");
if (!version = get_app_version(cpe: CPE, nofork: TRUE))
exit(0);
check_vers = ereg_replace(pattern: "(\(|\))", string: version, replace: ".");
check_vers = ereg_replace(pattern: "\.$", string: check_vers, replace: "");
affected = make_list(
"8.0.1.2",
"8.0.2",
"8.0.2.11",
"8.0.2.15",
"8.0.3",
"8.0.3.12",
"8.0.3.19",
"8.0.3.6",
"8.0.4",
"8.0.4.16",
"8.0.4.23",
"8.0.4.25",
"8.0.4.28",
"8.0.4.3",
"8.0.4.31",
"8.0.4.32",
"8.0.4.33",
"8.0.4.9",
"8.0.5",
"8.0.5.20",
"8.0.5.23",
"8.0.5.25",
"8.0.5.27",
"8.0.5.28",
"8.0.5.31",
"8.1.0.104",
"8.1.1",
"8.1.1.6",
"8.1.2",
"8.1.2.13",
"8.1.2.15",
"8.1.2.16",
"8.1.2.19",
"8.1.2.23",
"8.1.2.24",
"8.1.2.49",
"8.1.2.50",
"8.1.2.55",
"8.1.2.56",
"8.2.0.45",
"8.2.1",
"8.2.1.11",
"8.2.2",
"8.2.2.10",
"8.2.2.12",
"8.2.2.16",
"8.2.2.17",
"8.2.2.9",
"8.2.3",
"8.2.4",
"8.2.4.1",
"8.2.4.4",
"8.2.5",
"8.2.5.13",
"8.2.5.22",
"8.2.5.26",
"8.2.5.33",
"8.2.5.40",
"8.2.5.41",
"8.2.5.46",
"8.2.5.48",
"8.2.5.50",
"8.2.5.52",
"8.2.5.55",
"8.2.5.57",
"8.2.5.59",
"8.3.1",
"8.3.1.1",
"8.3.1.4",
"8.3.1.6",
"8.3.2",
"8.3.2.13",
"8.3.2.23",
"8.3.2.25",
"8.3.2.31",
"8.3.2.33",
"8.3.2.34",
"8.3.2.37",
"8.3.2.39",
"8.3.2.4",
"8.3.2.40",
"8.3.2.41",
"8.3.2.44",
"8.4.0",
"8.4.1",
"8.4.1.11",
"8.4.1.3",
"8.4.2",
"8.4.2.1",
"8.4.2.8",
"8.4.3",
"8.4.3.8",
"8.4.3.9",
"8.4.4",
"8.4.4.1",
"8.4.4.3",
"8.4.4.5",
"8.4.4.9",
"8.4.5",
"8.4.5.6",
"8.4.6",
"8.4.7",
"8.4.7.15",
"8.4.7.22",
"8.4.7.23",
"8.4.7.26",
"8.4.7.28",
"8.4.7.29",
"8.4.7.3",
"8.5.1",
"8.5.1.1",
"8.5.1.14",
"8.5.1.17",
"8.5.1.18",
"8.5.1.19",
"8.5.1.21",
"8.5.1.24",
"8.5.1.6",
"8.5.1.7",
"8.6.1",
"8.6.1.1",
"8.6.1.10",
"8.6.1.12",
"8.6.1.13",
"8.6.1.14",
"8.6.1.17",
"8.6.1.2",
"8.6.1.5",
"8.7.1",
"8.7.1.1",
"8.7.1.11",
"8.7.1.13",
"8.7.1.16",
"8.7.1.17",
"8.7.1.3",
"8.7.1.4",
"8.7.1.7",
"8.7.1.8",
"9.0.1",
"9.0.2",
"9.0.2.10",
"9.0.3",
"9.0.3.6",
"9.0.3.8",
"9.0.4",
"9.0.4.1",
"9.0.4.17",
"9.0.4.20",
"9.0.4.24",
"9.0.4.26",
"9.0.4.29",
"9.0.4.33",
"9.0.4.35",
"9.0.4.37",
"9.0.4.40",
"9.0.4.42",
"9.0.4.5",
"9.0.4.7",
"9.1.1",
"9.1.1.4",
"9.1.2",
"9.1.2.8",
"9.1.3",
"9.1.3.2",
"9.1.4",
"9.1.4.5",
"9.1.5",
"9.1.5.10",
"9.1.5.12",
"9.1.5.15",
"9.1.5.21",
"9.1.6",
"9.1.6.1",
"9.1.6.10",
"9.1.6.4",
"9.1.6.6",
"9.1.6.8",
"9.1.7.11",
"9.1.7.12",
"9.1.7.4",
"9.1.7.6",
"9.1.7.7",
"9.1.7.9",
"9.2.0.0",
"9.2.0.104",
"9.2.3.1",
"9.2.1",
"9.2.2",
"9.2.2.4",
"9.2.2.7",
"9.2.2.8",
"9.2.3",
"9.2.3.3",
"9.2.3.4",
"9.2.4",
"9.2.4.10",
"9.2.4.13",
"9.2.4.14",
"9.2.4.16",
"9.2.4.17",
"9.2.4.2",
"9.2.4.4",
"9.2.4.8",
"9.3.1.105",
"9.3.1.50",
"9.3.2.100",
"9.3.2.243",
"9.3.1",
"9.3.1.1",
"9.3.2",
"9.3.2.2",
"9.3.3",
"9.3.3.1",
"9.3.3.10",
"9.3.3.11",
"9.3.3.2",
"9.3.3.5",
"9.3.3.6",
"9.3.3.9",
"9.3.5",
"9.4.0.115",
"9.4.1",
"9.4.1.1",
"9.4.1.2",
"9.4.1.3",
"9.4.1.5",
"9.4.2",
"9.4.2.3",
"9.4.3",
"9.4.3.11",
"9.4.3.12",
"9.4.3.3",
"9.4.3.4",
"9.4.3.6",
"9.4.3.8",
"9.4.4",
"9.5.1",
"9.5.2",
"9.5.2.10",
"9.5.2.14",
"9.5.2.6",
"9.5.3",
"9.5.3.2",
"9.5.3.3",
"9.6.0",
"9.6.1",
"9.6.1.10",
"9.6.1.3",
"9.6.1.5",
"9.6.2",
"9.6.2.1",
"9.6.2.2",
"9.6.2.3");
foreach af (affected) {
if (check_vers == af) {
report = report_fixed_ver(installed_version: version, fixed_version: "See advisory");
security_message(port: 0, data: report);
exit(0);
}
}
exit(99);
CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:M/Au:N/C:N/I:N/A:P
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
LOW
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:L
AI Score
Confidence
High
EPSS
Percentile
60.4%