ntpd in NTP 4.x before 4.2.8p8, when autokey is enabled, allows remote attackers to cause a denial of service (peer-variable clearing and association outage) by sending (1) a spoofed crypto-NAK packet or (2) a packet with an incorrect MAC value at a certain time.
This plugin only works with Tenable.ot.
Please visit https://www.tenable.com/products/tenable-ot for more information.
#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##
include('compat.inc');
if (description)
{
script_id(501096);
script_version("1.3");
script_set_attribute(attribute:"plugin_modification_date", value:"2024/04/22");
script_cve_id("CVE-2016-4955");
script_xref(name:"SuSE", value:"openSUSE-SU-2016:1583");
script_xref(name:"SuSE", value:"SUSE-SU-2016:1563");
script_xref(name:"SuSE", value:"SUSE-SU-2016:1584");
script_xref(name:"SuSE", value:"SUSE-SU-2016:1602");
script_xref(name:"SuSE", value:"openSUSE-SU-2016:1636");
script_xref(name:"GLSA", value:"GLSA-201607-15");
script_xref(name:"FREEBSD", value:"FreeBSD-SA-16:24");
script_name(english:"Siemens SIMATIC NET CP 443-1 OPC UA Concurrent Execution Using Shared Resource with Improper Synchronization (CVE-2016-4955)");
script_set_attribute(attribute:"synopsis", value:
"The remote OT asset is affected by a vulnerability.");
script_set_attribute(attribute:"description", value:
"ntpd in NTP 4.x before 4.2.8p8, when autokey is enabled, allows remote
attackers to cause a denial of service (peer-variable clearing and
association outage) by sending (1) a spoofed crypto-NAK packet or (2)
a packet with an incorrect MAC value at a certain time.
This plugin only works with Tenable.ot.
Please visit https://www.tenable.com/products/tenable-ot for more information.");
script_set_attribute(attribute:"see_also", value:"http://www.kb.cert.org/vuls/id/321640");
script_set_attribute(attribute:"see_also", value:"http://support.ntp.org/bin/view/Main/NtpBug3043");
script_set_attribute(attribute:"see_also", value:"http://bugs.ntp.org/3043");
script_set_attribute(attribute:"see_also", value:"http://support.ntp.org/bin/view/Main/SecurityNotice");
# http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00023.html
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?cb7c151d");
# http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00018.html
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?f03b0a18");
# http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00024.html
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?cebdff21");
# http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00028.html
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?acf30d43");
# http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00040.html
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?7bcd4367");
# http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?eb5f426b");
script_set_attribute(attribute:"see_also", value:"http://www.securityfocus.com/bid/91007");
script_set_attribute(attribute:"see_also", value:"https://security.gentoo.org/glsa/201607-15");
script_set_attribute(attribute:"see_also", value:"https://www.cisa.gov/news-events/ics-advisories/icsa-21-159-11");
script_set_attribute(attribute:"see_also", value:"http://www.securitytracker.com/id/1036037");
script_set_attribute(attribute:"see_also", value:"https://security.FreeBSD.org/advisories/FreeBSD-SA-16:24.ntp.asc");
script_set_attribute(attribute:"see_also", value:"https://cert-portal.siemens.com/productcert/pdf/ssa-211752.pdf");
script_set_attribute(attribute:"solution", value:
"The following text was originally created by the Cybersecurity and Infrastructure Security Agency (CISA). The original
can be found at CISA.gov.
Siemens has identified the following specific workarounds and mitigations users can apply to reduce the risk:
- Deactivate NTP-based time synchronization of the device, if enabled. The feature is disabled by default.
- Configure an additional firewall to prevent communication to Port UDP/123 of an affected device.
As a general security measure, Siemens strongly recommends users protect network access to devices with appropriate
mechanisms. In order to operate the devices in a protected IT environment, Siemens recommends users configure the
environment according to Siemens operational guidelines for industrial security, and follow the recommendations in the
product manual.
Additional information on industrial security by Siemens can be found at: https://www.siemens.com/industrialsecurity
For more information about this issue, please see Siemens security advisory SSA-211752");
script_set_cvss_base_vector("CVSS2#AV:N/AC:M/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:H/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-2016-4955");
script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
script_cwe_id(362);
script_set_attribute(attribute:"vuln_publication_date", value:"2016/07/05");
script_set_attribute(attribute:"patch_publication_date", value:"2016/07/05");
script_set_attribute(attribute:"plugin_publication_date", value:"2023/05/02");
script_set_attribute(attribute:"plugin_type", value:"remote");
script_set_attribute(attribute:"cpe", value:"cpe:/o:siemens:simatic_net_cp_443-1_opc_ua_firmware");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"Tenable.ot");
script_copyright(english:"This script is Copyright (C) 2023-2024 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("tenable_ot_api_integration.nasl");
script_require_keys("Tenable.ot/Siemens");
exit(0);
}
include('tenable_ot_cve_funcs.inc');
get_kb_item_or_exit('Tenable.ot/Siemens');
var asset = tenable_ot::assets::get(vendor:'Siemens');
var vuln_cpes = {
"cpe:/o:siemens:simatic_net_cp_443-1_opc_ua_firmware" :
{"family" : "S7400"}
};
tenable_ot::cve::compare_and_report(asset:asset, cpes:vuln_cpes, severity:SECURITY_WARNING);
Vendor | Product | Version | CPE |
---|---|---|---|
siemens | simatic_net_cp_443-1_opc_ua_firmware | cpe:/o:siemens:simatic_net_cp_443-1_opc_ua_firmware |
bugs.ntp.org/3043
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-4955
support.ntp.org/bin/view/Main/NtpBug3043
support.ntp.org/bin/view/Main/SecurityNotice
www.kb.cert.org/vuls/id/321640
www.nessus.org/u?7bcd4367
www.nessus.org/u?acf30d43
www.nessus.org/u?cb7c151d
www.nessus.org/u?cebdff21
www.nessus.org/u?eb5f426b
www.nessus.org/u?f03b0a18
www.securityfocus.com/bid/91007
www.securitytracker.com/id/1036037
cert-portal.siemens.com/productcert/pdf/ssa-211752.pdf
security.FreeBSD.org/advisories/FreeBSD-SA-16:24.ntp.asc
security.gentoo.org/glsa/201607-15
www.cisa.gov/news-events/ics-advisories/icsa-21-159-11