IBM SECURITY ADVISORY

First Issued: Tue Feb 24 11:33:18 CST 2015

The most recent version of this document is available here:

http://aix.software.ibm.com/aix/efixes/security/bind9_advisory7.asc
https://aix.software.ibm.com/aix/efixes/security/bind9_advisory7.asc
ftp://aix.software.ibm.com/aix/efixes/security/bind9_advisory7.asc

                       VULNERABILITY SUMMARY

VULNERABILITY: Vulnerability in AIX bind

PLATFORMS: AIX 5.3, 6.1, and 7.1 releases
VIOS 2.2.*

SOLUTION: Apply the fix as described below

THREAT: A remote attacker can cause denial of service

CVE Number: CVE-2014-8500 CVSS=7.80

Reboot required? NO
Workarounds? NO
Protected by FPM? NO
Protected by SED? NO

===============================================================================
DETAILED INFORMATION

I. DESCRIPTION (from cve.mitre.org)

CVE-2014-8500
ISC BIND 9.0.x through 9.8.x, 9.9.0 through 9.9.6, and 9.10.0 through
9.10.1 does not limit delegation chaining, which allows remote attackers
to cause a denial of service (memory consumption and named crash) via a
large or infinite number of referrals. 

Please see following for more information:

https://vulners.com/cve/CVE-2014-8500

II. CVSS

CVE-2014-8500 
CVSS Base Score: 7.80
CVSS Temporal Score: See http://xforce.iss.net/xforce/xfdb/99187 for the
current score
CVSS Environmental Score*: Undefined
CVSS String: (AV:N/AC:L/Au:N/C:N/I:N/A:C)

III. PLATFORM VULNERABILITY ASSESSMENT

Note: To use the following commands on VIOS you must first
execute:

oem_setup_env

To determine if your system is vulnerable, execute the following
command:

lslpp -L bos.net.tcp.client
lslpp -L bos.net.tcp.server

The following fileset levels are vulnerable:

AIX Fileset        Lower Level       Upper Level   KEY
----------------------------------------------------------
bos.net.tcp.server  5.3.12.0         5.3.12.6     key_w_fs
bos.net.tcp.server  6.1.8.0          6.1.8.18     key_w_fs
bos.net.tcp.server  6.1.9.0          6.1.9.30     key_w_fs
bos.net.tcp.server  7.1.2.0          7.1.2.18     key_w_fs
bos.net.tcp.server  7.1.3.0          7.1.3.30     key_w_fs
bos.net.tcp.client  5.3.12.0         5.3.12.10    key_w_fs
bos.net.tcp.client  6.1.8.0          6.1.8.19     key_w_fs
bos.net.tcp.client  6.1.9.0          6.1.9.30     key_w_fs
bos.net.tcp.client  7.1.2.0          7.1.2.19     key_w_fs
bos.net.tcp.client  7.1.3.0          7.1.3.30     key_w_fs


AIX Fileset (VIOS)  Lower Level           Upper Level
----------------------------------------------------------------
bos.net.tcp.server  6.1.8.0(2.2.2.0)      6.1.8.18(2.2.2.4)
bos.net.tcp.server  6.1.9.0(2.2.3.0)      6.1.9.30(2.2.3.4)
bos.net.tcp.client  6.1.8.0(2.2.2.0)      6.1.8.19(2.2.2.4)
bos.net.tcp.client  6.1.9.0(2.2.3.0)      6.1.9.30(2.2.3.4)

IV. SOLUTIONS

A. APARS

    IBM has assigned the following APARs to this problem:

    AIX Level      APAR number   Availability      KEY
    -------------------------------------------------------------
    5.3.12         IV68997       ifix_only n/a         key_w_apar
    6.1.8          IV68993       09/30/2015 SP7        key_w_apar
    6.1.9          IV68994       05/29/2015 SP5        key_w_apar
    7.1.2          IV68995       09/30/2015 SP7        key_w_apar
    7.1.3          IV68996       05/29/2015 SP5        key_w_apar

    Subscribe to the APARs here:

    http://www.ibm.com/support/docview.wss?uid=isg1IV68997
    http://www.ibm.com/support/docview.wss?uid=isg1IV68993
    http://www.ibm.com/support/docview.wss?uid=isg1IV68994
    http://www.ibm.com/support/docview.wss?uid=isg1IV68995
    http://www.ibm.com/support/docview.wss?uid=isg1IV68996

    By subscribing, you will receive periodic email alerting you
    to the status of the APAR, and a link to download the fix once
    it becomes available.

B. FIXES

    Fixes are available.  The fixes can be downloaded via ftp
    from:

    ftp://aix.software.ibm.com/aix/efixes/security/bind9_fix7.tar

    The link above is to a tar file containing this signed
    advisory, fix packages, and PGP signatures for each package.
    The fixes below include prerequisite checking. This will
    enforce the correct mapping between the fixes and AIX
    Technology Levels.

    AIX Level   Interim Fix (*.Z)            KEY
    --------------------------------------------------
    5.3.12.9    IV68997m9a.150129.epkg.Z     key_w_fix
    6.1.8.6     IV68993s6a.150129.epkg.Z     key_w_fix
    6.1.9.4     IV68994s4a.150129.epkg.Z     key_w_fix
    7.1.2.6     IV68995s6a.150129.epkg.Z     key_w_fix
    7.1.3.4     IV68996s4a.150129.epkg.Z     key_w_fix

    VIOS Level   Interim Fix (*.Z)
    -------------------------------------
    2.2.2.4      IV68993s6a.150129.epkg.Z 
    2.2.3.4      IV68994s4a.150129.epkg.Z 

    To extract the fixes from the tar file:
    tar -xvf bind9_fix7.tar
    cd bind9_fix7

    Verify you have retrieved the fixes intact:

	The checksums below were generated using the
    "openssl dgst -sha256 file" command as the followng:

    openssl dgst -sha256                                             filename                 KEY
    ----------------------------------------------------------------------------------------------------
    9ffc09d88a41825b64e28c1847a3428f724fd6215be7bcffc9f8427b70d7f6b1 IV68997m9a.150129.epkg.Z key_w_csum 
    9aedad84518e61d3a49f2853bdb0710228d9ebfdeae2defe9a323076f333177d IV68993s6a.150129.epkg.Z key_w_csum
    3882d8cec4e886055e53337ac123dd1c06481063762458c33363d43ec926b206 IV68994s4a.150129.epkg.Z key_w_csum	
    f2999e2fd1eb5bce8274bf08860a88e08485ae1c62d3d089733e84f5164e335d IV68995s6a.150129.epkg.Z key_w_csum
    e4ef39e4445624656c4f0ae33985a537b2172feb8ea6fa2b72be67ae819360b4 IV68996s4a.150129.epkg.Z key_w_csum

    These sums should match exactly. The OpenSSL signatures in the tar
    file and on this advisory can also be used to verify the
    integrity of the fixes.  If the sums or signatures cannot be
    confirmed, contact IBM AIX Security at
    [email protected] and describe the discrepancy.

    openssl dgst -sha1 -verify <pubkey_file> -signature <advisory_file>.sig <advisory_file>

    openssl dgst -sha1 -verify <pubkey_file> -signature <ifix_file>.sig <ifix_file>

 C. FIX AND INTERIM FIX INSTALLATION

    IMPORTANT: If possible, it is recommended that a mksysb backup
    of the system be created.  Verify it is both bootable and
    readable before proceeding.

    To preview a fix installation:

    installp -a -d fix_name -p all  # where fix_name is the name of the
                                    # fix package being previewed.
    To install a fix package:

    installp -a -d fix_name -X all  # where fix_name is the name of the
                                    # fix package being installed.

    Interim fixes have had limited functional and regression
    testing but not the full regression testing that takes place
    for Service Packs; however, IBM does fully support them.

    Interim fix management documentation can be found at:

    http://www14.software.ibm.com/webapp/set2/sas/f/aix.efixmgmt/home.html

    To preview an interim fix installation:

    emgr -e ipkg_name -p         # where ipkg_name is the name of the
                                 # interim fix package being previewed.

    To install an interim fix package:

    emgr -e ipkg_name -X         # where ipkg_name is the name of the
                                 # interim fix package being installed.

V. WORKAROUNDS (from kb.isc.org)
None.

VI. OBTAINING FIXES

AIX security fixes can be downloaded from:

    ftp://aix.software.ibm.com/aix/efixes/security

AIX fixes can be downloaded from:

    http://www.ibm.com/eserver/support/fixes/fixcentral/main/pseries/aix

NOTE: Affected customers are urged to upgrade to the latest
applicable Technology Level and Service Pack.

VII. CONTACT INFORMATION

If you would like to receive AIX Security Advisories via email,
please visit "My Notifications":

     http://www.ibm.com/support/mynotifications

and click on the "My notifications" link.

To view previously issued advisories, please visit:

    http://www14.software.ibm.com/webapp/set2/subscriptions/onvdq

Comments regarding the content of this announcement can be
directed to:

    [email protected]

To obtain the OpenSSL public key that can be used to verify the
signed advisories and ifixes:

    Download the key from our web page:

    http://www.ibm.com/systems/resources/systems_p_os_aix_security_pgpkey.txt

To obtain the PGP public key that can be used to communicate
securely with the AIX Security Team you can either:

    A. Send an email with "get key" in the subject line to:

        [email protected]

    B. Download the key from a PGP Public Key Server. The key ID is:

        0x28BFAA12

Please contact your local IBM AIX support center for any
assistance.

VIII. ACKNOWLEDGMENTS
N/A.

IX. REFERENCES:

Complete CVSS Guide: http://www.first.org/cvss/cvss-guide.html
On-line Calculator V2: http://nvd.nist.gov/cvss.cfm?calculator&adv&version=2
X-Force Vulnerability Database: http://xforce.iss.net/xforce/xfdb/
CVE-2014-8500: https://vulners.com/cve/CVE-2014-8500

*The CVSS Environment Score is customer environment specific and will
ultimately impact the Overall CVSS Score. Customers can evaluate the
impact of this vulnerability in their environments by accessing the links
in the Reference section of this Flash.

Note: According to the Forum of Incident Response and Security Teams
(FIRST), the Common Vulnerability Scoring System (CVSS) is an "industry
open standard designed to convey vulnerability severity and help to
determine urgency and priority of response." IBM PROVIDES THE CVSS SCORES
"AS IS" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. CUSTOMERS ARE
RESPONSIBLE FOR ASSESSING THE IMPACT OF ANY ACTUAL OR POTENTIAL SECURITY
VULNERABILITY.