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: http://cve.mitre.org/cgi-bin/cvename.cgi?name=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 security-alert@austin.ibm.com and describe the discrepancy. openssl dgst -sha1 -verify -signature .sig openssl dgst -sha1 -verify -signature .sig 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: security-alert@austin.ibm.com 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: security-alert@austin.ibm.com 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: http://cve.mitre.org/cgi-bin/cvename.cgi?name=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.