7.5 High
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:P/I:P/A:P
9.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
0.86 High
EPSS
Percentile
98.6%
The version of the remote NTP server is 3.x or 4.x prior to 4.2.8p7.
It is, therefore, affected by the following vulnerabilities :
A denial of service vulnerability exists due to improper validation of the origin timestamp field when handling a Kiss-of-Death (KoD) packet. An unauthenticated, remote attacker can exploit this to cause a client to stop querying its servers, preventing the client from updating its clock. (CVE-2015-7704)
A flaw exists in the receive() function in ntp_proto.c that allows packets with an origin timestamp of zero to bypass security checks. An unauthenticated, remote attacker can exploit this to spoof arbitrary content.
(CVE-2015-8138)
A denial of service vulnerability exists due to improper handling of a crafted Crypto NAK Packet with a source address spoofed to match that of an existing associated peer. An unauthenticated, remote attacker can exploit this to demobilize a client association. (CVE-2016-1547)
A denial of service vulnerability exists due to improper handling of packets spoofed to appear to be from a valid ntpd server. An unauthenticated, remote attacker can exploit this to cause NTP to switch from basic client/server mode to interleaved symmetric mode, causing the client to reject future legitimate responses. (CVE-2016-1548)
A race condition exists that is triggered during the handling of a saturation of ephemeral associations. An authenticated, remote attacker can exploit this to defeat NTP’s clock selection algorithm and modify a user’s clock. (CVE-2016-1549)
An information disclosure vulnerability exists in the message authentication functionality in libntp that is triggered during the handling of a series of specially crafted messages. An adjacent attacker can exploit this to partially recover the message digest key.
(CVE-2016-1550)
A flaw exists due to improper filtering of IPv4 ‘bogon’ packets received from a network. An unauthenticated, remote attacker can exploit this to spoof packets to appear to come from a specific reference clock.
(CVE-2016-1551)
A denial of service vulnerability exists that allows an authenticated, remote attacker that has knowledge of the controlkey for ntpq or the requestkey for ntpdc to create a session with the same IP twice on an unconfigured directive line, causing ntpd to abort.
(CVE-2016-2516)
A denial of service vulnerability exists that allows an authenticated, remote attacker to manipulate the value of the trustedkey, controlkey, or requestkey via a crafted packet, preventing authentication with ntpd until the daemon has been restarted. (CVE-2016-2517)
An out-of-bounds read error exists in the MATCH_ASSOC() function that occurs during the creation of peer associations with hmode greater than 7. An authenticated, remote attacker can exploit this, via a specially crafted packet, to cause a denial of service.
(CVE-2016-2518)
An overflow condition exists in the ctl_getitem() function in ntpd due to improper validation of user-supplied input when reporting return values. An authenticated, remote attacker can exploit this to cause ntpd to abort. (CVE-2016-2519)
#
# (C) Tenable Network Security, Inc.
#
include("compat.inc");
if (description)
{
script_id(90923);
script_version("1.15");
script_cvs_date("Date: 2019/11/19");
script_cve_id(
"CVE-2015-7704",
"CVE-2015-7705",
"CVE-2015-7974",
"CVE-2015-8138",
"CVE-2016-1547",
"CVE-2016-1548",
"CVE-2016-1549",
"CVE-2016-1550",
"CVE-2016-1551",
"CVE-2016-2516",
"CVE-2016-2517",
"CVE-2016-2518",
"CVE-2016-2519"
);
script_bugtraq_id(
88180,
88189,
88200,
88204,
88219,
88226,
88261,
88264,
88276
);
script_xref(name:"CERT", value:"718152");
script_name(english:"Network Time Protocol Daemon (ntpd) 3.x / 4.x < 4.2.8p7 Multiple Vulnerabilities");
script_summary(english:"Checks for a vulnerable NTP server.");
script_set_attribute(attribute:"synopsis", value:
"The remote NTP server is affected by multiple vulnerabilities.");
script_set_attribute(attribute:"description", value:
"The version of the remote NTP server is 3.x or 4.x prior to 4.2.8p7.
It is, therefore, affected by the following vulnerabilities :
- A denial of service vulnerability exists due to improper
validation of the origin timestamp field when handling a
Kiss-of-Death (KoD) packet. An unauthenticated, remote
attacker can exploit this to cause a client to stop
querying its servers, preventing the client from
updating its clock. (CVE-2015-7704)
- A flaw exists in the receive() function in ntp_proto.c
that allows packets with an origin timestamp of zero to
bypass security checks. An unauthenticated, remote
attacker can exploit this to spoof arbitrary content.
(CVE-2015-8138)
- A denial of service vulnerability exists due to improper
handling of a crafted Crypto NAK Packet with a source
address spoofed to match that of an existing associated
peer. An unauthenticated, remote attacker can exploit
this to demobilize a client association. (CVE-2016-1547)
- A denial of service vulnerability exists due to improper
handling of packets spoofed to appear to be from a valid
ntpd server. An unauthenticated, remote attacker can
exploit this to cause NTP to switch from basic
client/server mode to interleaved symmetric mode,
causing the client to reject future legitimate
responses. (CVE-2016-1548)
- A race condition exists that is triggered during the
handling of a saturation of ephemeral associations. An
authenticated, remote attacker can exploit this to
defeat NTP's clock selection algorithm and modify a
user's clock. (CVE-2016-1549)
- An information disclosure vulnerability exists in the
message authentication functionality in libntp that is
triggered during the handling of a series of specially
crafted messages. An adjacent attacker can exploit this
to partially recover the message digest key.
(CVE-2016-1550)
- A flaw exists due to improper filtering of IPv4 'bogon'
packets received from a network. An unauthenticated,
remote attacker can exploit this to spoof packets to
appear to come from a specific reference clock.
(CVE-2016-1551)
- A denial of service vulnerability exists that allows an
authenticated, remote attacker that has knowledge of the
controlkey for ntpq or the requestkey for ntpdc to
create a session with the same IP twice on an
unconfigured directive line, causing ntpd to abort.
(CVE-2016-2516)
- A denial of service vulnerability exists that allows an
authenticated, remote attacker to manipulate the value
of the trustedkey, controlkey, or requestkey via a
crafted packet, preventing authentication with ntpd
until the daemon has been restarted. (CVE-2016-2517)
- An out-of-bounds read error exists in the MATCH_ASSOC()
function that occurs during the creation of peer
associations with hmode greater than 7. An
authenticated, remote attacker can exploit this, via a
specially crafted packet, to cause a denial of service.
(CVE-2016-2518)
- An overflow condition exists in the ctl_getitem()
function in ntpd due to improper validation of
user-supplied input when reporting return values. An
authenticated, remote attacker can exploit this to cause
ntpd to abort. (CVE-2016-2519)");
script_set_attribute(attribute:"see_also", value:"http://support.ntp.org/bin/view/Main/SecurityNotice");
# http://support.ntp.org/bin/view/Main/SecurityNotice#April_2016_NTP_4_2_8p7_Security
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?4a6d1cf4");
script_set_attribute(attribute:"solution", value:
"Upgrade to NTP version 4.2.8p7 or later.");
script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/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:L/PR:N/UI:N/S:U/C:H/I:H/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-2015-7705");
script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
script_set_attribute(attribute:"exploit_available", value:"false");
script_set_attribute(attribute:"vuln_publication_date", value:"2015/10/06");
script_set_attribute(attribute:"patch_publication_date", value:"2016/04/26");
script_set_attribute(attribute:"plugin_publication_date", value:"2016/05/05");
script_set_attribute(attribute:"potential_vulnerability", value:"true");
script_set_attribute(attribute:"plugin_type", value:"remote");
script_set_attribute(attribute:"cpe", value:"cpe:/a:ntp:ntp");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"Misc.");
script_copyright(english:"This script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("ntp_open.nasl");
script_require_keys("NTP/Running", "Settings/ParanoidReport");
exit(0);
}
include("audit.inc");
include("global_settings.inc");
include("misc_func.inc");
# Make sure NTP server is running
get_kb_item_or_exit('NTP/Running');
app_name = "NTP Server";
port = get_kb_item("Services/udp/ntp");
if (!port) port = 123;
version = get_kb_item_or_exit("Services/ntp/version");
if (version == 'unknown') audit(AUDIT_UNKNOWN_APP_VER, app_name);
match = pregmatch(string:version, pattern:"([0-9a-z.]+)");
if (isnull(match) || empty_or_null(match[1])) audit(AUDIT_UNKNOWN_APP_VER, app_name);
# Paranoia check
if (report_paranoia < 2) audit(AUDIT_PARANOID);
ver = match[1];
verfields = split(ver, sep:".", keep:FALSE);
major = int(verfields[0]);
minor = int(verfields[1]);
if ('p' >< verfields[2])
{
revpatch = split(verfields[2], sep:"p", keep:FALSE);
rev = int(revpatch[0]);
patch = int(revpatch[1]);
}
else
{
rev = verfields[2];
patch = 0;
}
# This vulnerability affects NTP 3.x / 4.x < 4.2.8p7
if (
(major == 3) ||
(major == 4 && minor < 2) ||
(major == 4 && minor == 2 && rev < 8) ||
(major == 4 && minor == 2 && rev == 8 && patch < 7)
)
{
fix = "4.2.8p7";
}
else audit(AUDIT_INST_VER_NOT_VULN, app_name, version);
report =
'\n Installed version : ' + version +
'\n Fixed version : ' + fix +
'\n';
security_report_v4(
port : port,
proto : "udp",
extra : report,
severity : SECURITY_HOLE
);
exit(0);
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-7704
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-7705
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-7974
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-8138
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-1547
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-1548
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-1549
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-1550
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-1551
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2516
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2517
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2518
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2519
support.ntp.org/bin/view/Main/SecurityNotice
www.nessus.org/u?4a6d1cf4
7.5 High
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:P/I:P/A:P
9.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
0.86 High
EPSS
Percentile
98.6%