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NTP.org ntpd contains multiple vulnerabilities

Vulnerability Note VU#718152

Original Release Date: 2016-04-27 | Last Revised: 2016-04-28

Overview

The NTP.org reference implementation of ntpd contains multiple vulnerabilities.

Description

NTP.org's reference implementation of NTP server, ntpd, contains multiple vulnerabilities.

CWE-294: Authentication Bypass by Capture-replay - CVE-2015-7973

An attacker on the network can record and replay authenticated broadcast mode packets. Also known as the "Deja Vu" attack.

CWE-20: Improper Input Validation - CVE-2015-7974

A missing key check allows impersonation between authenticated peers. Also known as the "Skeleton Key" attack.

CWE-20: Improper Input Validation - CVE-2015-7975

The nextvar() function does not properly validate length.

CWE-20: Improper Input Validation - CVE-2015-7976

ntpq saveconfig command allows dangerous characters in filenames

CWE-476: NULL Pointer Dereference - CVE-2015-7977

reslist NULL pointer dereference

CWE-400: Uncontrolled Resource Consumption ('Resource Exhaustion') - CVE-2015-7978

Stack exhaustion in recursive traversal of restriction list

CWE-821: Incorrect Synchronization - CVE-2015-7979

Off-path Denial of Service (DoS) attack on authenticated broadcast and other pre-emptable modes

CWE-20: Improper Input Validation - CVE-2015-8138

Zero Origin Timestamp Bypass

CWE-200: Information Exposure - CVE-2015-8139

Network Time Protocol ntpq and ntpdc Origin Timestamp Disclosure Vulnerability
http://support.ntp.org/bin/view/Main/NtpBug2946

CWE-294: Authentication Bypass by Capture-replay - CVE-2015-8140

Network Time Protocol ntpq Control Protocol Replay Vulnerability
http://support.ntp.org/bin/view/Main/NtpBug2947

CWE-400: Uncontrolled Resource Consumption ('Resource Exhaustion') - CVE-2015-8158

Potential Infinite Loop in ntpq
http://support.ntp.org/bin/view/Main/NtpBug2948

CWE-821: Incorrect Synchronization - CVE-2016-1547

An off-path attacker can deny service to ntpd clients by demobilizing preemptable associations using spoofed crypto-NAK packets. This vulnerability involves different code paths than those used by CVE-2015-7979.

CWE-290: Authentication Bypass by Spoofing - CVE-2016-1548

By spoofing packets from a legitimate server, an attacker can change the time of an ntpd client or deny service to an ntpd client by forcing it to change from basic client/server mode to interleaved symmetric mode.

CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') - CVE-2016-1549

ntpd does not prevent Sybil attacks from authenticated peers. An malicious authenticated peer can create any number of ephemeral associations in order to win ntpd's clock selection algorithm and modify a victim's clock.

CWE-20: Improper Input Validation - CVE-2016-1550

ntpd does not use a constant-time memory comparison function when validating the authentication digest on incoming packets. In some situations this may allow an attacker to conduct a timing attack to compute the value of the valid authentication digest causing forged packets to be accepted by ntpd.

CWE-290: Authentication Bypass by Spoofing - CVE-2016-1551

ntpd does not filter IPv4 bogon packets received from the network. This allows unauthenticated network attackers to spoof refclock packets to ntpd processes on systems that do not implement bogon filtering.

CWE-20: Improper Input Validation - CVE-2016-2516, CVE-2016-2517

Duplicate IPs on unconfig directives will cause an assertion botch in ntpd. A regression caused by the patch for CVE-2016-2516 was fixed and identified as CVE-2016-2517.

CWE-125: Out-of-bounds Read - CVE-2016-2518

Using a crafted packet to create a peer association with hmode > 7 causes the MATCH_ASSOC() lookup to make an out-of-bounds reference.

CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer - CVE-2016-2519

ntpq and ntpdc can be used to store and retrieve information in ntpd. It is possible to store a data value that is larger than the size of the buffer that the ctl_getitem() function of ntpd uses to report the return value. If the length of the requested data value returned by ctl_getitem() is too large, the value NULL is returned instead. There are 2 cases where the return value from ctl_getitem() was not directly checked to make sure it's not NULL, but there are subsequent INSIST() checks that make sure the return value is not NULL. There are no data values ordinarily stored in ntpd that would exceed this buffer length. But if one has permission to store values and one stores a value that is "too large", then ntpd will abort if an attempt is made to read that oversized value.

CWE-20: Improper Input Validation - CVE-2015-7704, CVE-2015-7705

An ntpd client that honors Kiss-of-Death (KoD) responses will honor KoD messages that have been forged by an attacker, causing it to delay or stop querying its servers for time updates. Also, an attacker can forge packets that claim to be from the target and send them to servers often enough that a server that implements KoD rate limiting will send the target machine a KoD response to attempt to reduce the rate of incoming packets, or it may also trigger a firewall block at the server for packets from the target machine. For either of these attacks to succeed, the attacker must know what servers the target is communicating with. An attacker can be anywhere on the Internet and can frequently learn the identity of the target's time source by sending the target a time query.

For more information on these vulnerabilities, please see NTP.org's April 2016 security advisory as well as the January 2016 security advisory.

Impact

Unauthenticated remote attackers may be able to spoof packets to cause denial of service, authentication bypass on commands, or certain configuration changes. For more information on these vulnerabilities, please see NTP.org's April 2016 security advisory as well as the January 2016 security advisory.

Solution

Apply an update

Partial patches for some of these issues were initially released in January 2016 as version 4.2.8p6. Complete patches for all of these issues are now available in version 4.2.8p7, released 2016-04-26. Affected users are encouraged to update as soon as possible.

Vendor Information

718152
 
Affected   Unknown   Unaffected

NTP Project

Notified:  January 19, 2016 Updated:  April 22, 2016

Statement Date:   April 19, 2016

Status

  Affected

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

We are not aware of further vendor information regarding this vulnerability.

ACCESS

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

AT&T

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Alcatel-Lucent

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Apple

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Arista Networks, Inc.

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Aruba Networks

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Avaya, Inc.

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Belkin, Inc.

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Blue Coat Systems

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

CA Technologies

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

CentOS

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Check Point Software Technologies

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Cisco

Notified:  January 08, 2016 Updated:  January 08, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

CoreOS

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

D-Link Systems, Inc.

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Debian GNU/Linux

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

DesktopBSD

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

DragonFly BSD Project

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

EMC Corporation

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

EfficientIP SAS

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Enterasys Networks

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Ericsson

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Extreme Networks

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

F5 Networks, Inc.

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Fedora Project

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Force10 Networks

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

FreeBSD Project

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Gentoo Linux

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Google

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Hardened BSD

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Hewlett Packard Enterprise

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Hitachi

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Huawei Technologies

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

IBM Corporation

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

IBM eServer

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Infoblox

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Intel Corporation

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Internet Systems Consortium

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Internet Systems Consortium - DHCP

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Juniper Networks

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

McAfee

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Microsoft Corporation

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

NEC Corporation

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

NTPsec

Notified:  January 19, 2016 Updated:  January 19, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

NetBSD

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Nokia

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Nominum

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

OmniTI

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

OpenBSD

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

OpenDNS

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Openwall GNU/*/Linux

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Oracle Corporation

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Peplink

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Q1 Labs

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

QNX Software Systems Inc.

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Red Hat, Inc.

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

SUSE Linux

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

SafeNet

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Secure64 Software Corporation

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Slackware Linux Inc.

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

SmoothWall

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Snort

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Sony Corporation

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Sourcefire

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Symantec

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

TippingPoint Technologies Inc.

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Turbolinux

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Ubuntu

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Unisys

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

VMware

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Wind River

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

dnsmasq

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

m0n0wall

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

openSUSE project

Notified:  April 25, 2016 Updated:  April 25, 2016

Status

  Unknown

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

View all 75 vendors View less vendors


CVSS Metrics

Group Score Vector
Base 6.8 AV:N/AC:M/Au:N/C:P/I:P/A:P
Temporal 5.3 E:POC/RL:OF/RC:C
Environmental 5.3 CDP:ND/TD:H/CR:ND/IR:ND/AR:ND

References

Credit

Thanks to Cisco TALOS for reporting many of these issues to us. The Network Time Foundation credits many researchers for these vulnerabilities; see NTP.org's January 2016 and April 2016 security advisories for the complete list.

This document was written by Garret Wassermann.

Other Information

Sponsored by the Department of Homeland Security Office of Cybersecurity and Communications.