what you don't know can hurt you
Home Files News &[SERVICES_TAB]About Contact Add New

FreeBSD Security Advisory - ntp Issues

FreeBSD Security Advisory - ntp Issues
Posted Apr 8, 2015
Site security.freebsd.org

FreeBSD Security Advisory - The ntpd(8) daemon is an implementation of the Network Time Protocol (NTP) used to synchronize the time of a computer system to a reference time source. The vallen packet value is not validated in several code paths in ntp_crypto.c. When ntpd(8) is configured to use a symmetric key to authenticate a remote NTP server/peer, it checks if the NTP message authentication code (MAC) in received packets is valid, but not that there actually is any MAC included, and packets without a MAC are accepted as if they had a valid MAC. NTP state variables are updated prior to validating the received packets.

tags | advisory, remote, protocol
systems | freebsd
advisories | CVE-2014-9297, CVE-2015-1798, CVE-2015-1799
SHA-256 | 76984f9165afa07a2ac44484102a158a9baadc4ba9f94cabfb3ef94b8f0fb933

FreeBSD Security Advisory - ntp Issues

Change Mirror Download
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA512

=============================================================================
FreeBSD-SA-15:07.ntp Security Advisory
The FreeBSD Project

Topic: Multiple vulnerabilities of ntp

Category: contrib
Module: ntp
Announced: 2015-04-07
Credits: Network Time Foundation
Affects: All supported versions of FreeBSD.
Corrected: 2015-04-07 20:20:24 UTC (stable/10, 10.1-STABLE)
2015-04-07 20:21:01 UTC (releng/10.1, 10.1-RELEASE-p9)
2015-04-07 20:20:44 UTC (stable/9, 9.3-STABLE)
2015-04-07 20:21:23 UTC (releng/9.3, 9.3-RELEASE-p13)
2015-04-07 20:20:44 UTC (stable/8, 8.4-STABLE)
2015-04-07 20:21:23 UTC (releng/8.4, 8.4-RELEASE-p27)
CVE Name: CVE-2014-9297, CVE-2015-1798, CVE-2015-1799

For general information regarding FreeBSD Security Advisories,
including descriptions of the fields above, security branches, and the
following sections, please visit <URL:https://security.FreeBSD.org/>.

I. Background

The ntpd(8) daemon is an implementation of the Network Time Protocol (NTP)
used to synchronize the time of a computer system to a reference time
source.

II. Problem Description

The vallen packet value is not validated in several code paths in
ntp_crypto.c. [CVE-2014-9297]

When ntpd(8) is configured to use a symmetric key to authenticate a remote
NTP server/peer, it checks if the NTP message authentication code (MAC)
in received packets is valid, but not that there actually is any MAC
included, and packets without a MAC are accepted as if they had a valid
MAC. [CVE-2015-1798]

NTP state variables are updated prior to validating the received packets.
[CVE-2015-1799]

III. Impact

A remote attacker who can send specifically crafted packets may be able
to reveal memory contents of ntpd(8) or cause it to crash, when ntpd(8)
is configured to use autokey. [CVE-2014-9297]

A man-in-the-middle (MITM) attacker can send specially forged packets
that would be accepted by the client/peer without having to know the
symmetric key. [CVE-2015-1798]

An attacker knowing that NTP hosts A and B are peering with each other
(symmetric association) can periodically send a specially crafted or
replayed packet which will break the synchronization between the two
peers due to transmit timestamp mismatch, preventing the two nodes from
synchronizing with each other, even when authentication is enabled.
[CVE-2015-1799]

IV. Workaround

No workaround is available, but systems not running ntpd(8) are not
affected.

V. Solution

Perform one of the following:

1) Upgrade your vulnerable system to a supported FreeBSD stable or
release / security branch (releng) dated after the correction date.

2) To update your vulnerable system via a binary patch:

Systems running a RELEASE version of FreeBSD on the i386 or amd64
platforms can be updated via the freebsd-update(8) utility:

# freebsd-update fetch
# freebsd-update install

3) To update your vulnerable system via a source code patch:

The following patches have been verified to apply to the applicable
FreeBSD release branches.

a) Download the relevant patch from the location below, and verify the
detached PGP signature using your PGP utility.

# fetch https://security.FreeBSD.org/patches/SA-15:07/ntp.patch
# fetch https://security.FreeBSD.org/patches/SA-15:07/ntp.patch.asc
# gpg --verify ntp.patch.asc

b) Apply the patch. Execute the following commands as root:

# cd /usr/src
# patch < /path/to/patch

c) Recompile the operating system using buildworld and installworld as
described in <URL:https://www.FreeBSD.org/handbook/makeworld.html>.

Restart the applicable daemons, or reboot the system.

VI. Correction details

The following list contains the correction revision numbers for each
affected branch.

Branch/path Revision
- -------------------------------------------------------------------------
stable/8/ r281231
releng/8.4/ r281233
stable/9/ r281231
releng/9.3/ r281233
stable/10/ r281230
releng/10.1/ r281232
- -------------------------------------------------------------------------

To see which files were modified by a particular revision, run the
following command, replacing NNNNNN with the revision number, on a
machine with Subversion installed:

# svn diff -cNNNNNN --summarize svn://svn.freebsd.org/base

Or visit the following URL, replacing NNNNNN with the revision number:

<URL:https://svnweb.freebsd.org/base?view=revision&revision=NNNNNN>

VII. References

<URL:https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2014-9297>

<URL:https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-1798>

<URL:https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-1799>

The latest revision of this advisory is available at
<URL:https://security.FreeBSD.org/advisories/FreeBSD-SA-15:07.ntp.asc>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.1.2 (FreeBSD)
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=1fHm
-----END PGP SIGNATURE-----
Login or Register to add favorites

File Archive:

February 2024

  • Su
  • Mo
  • Tu
  • We
  • Th
  • Fr
  • Sa
  • 1
    Feb 1st
    16 Files
  • 2
    Feb 2nd
    19 Files
  • 3
    Feb 3rd
    0 Files
  • 4
    Feb 4th
    0 Files
  • 5
    Feb 5th
    24 Files
  • 6
    Feb 6th
    2 Files
  • 7
    Feb 7th
    10 Files
  • 8
    Feb 8th
    25 Files
  • 9
    Feb 9th
    37 Files
  • 10
    Feb 10th
    0 Files
  • 11
    Feb 11th
    0 Files
  • 12
    Feb 12th
    17 Files
  • 13
    Feb 13th
    20 Files
  • 14
    Feb 14th
    25 Files
  • 15
    Feb 15th
    15 Files
  • 16
    Feb 16th
    6 Files
  • 17
    Feb 17th
    0 Files
  • 18
    Feb 18th
    0 Files
  • 19
    Feb 19th
    35 Files
  • 20
    Feb 20th
    25 Files
  • 21
    Feb 21st
    18 Files
  • 22
    Feb 22nd
    15 Files
  • 23
    Feb 23rd
    0 Files
  • 24
    Feb 24th
    10 Files
  • 25
    Feb 25th
    0 Files
  • 26
    Feb 26th
    37 Files
  • 27
    Feb 27th
    34 Files
  • 28
    Feb 28th
    27 Files
  • 29
    Feb 29th
    0 Files

Top Authors In Last 30 Days

File Tags

Systems

packet storm

© 2022 Packet Storm. All rights reserved.

Services
Security Services
Hosting By
Rokasec
close