IBM SECURITY ADVISORY First Issued: Mon Apr 18 10:40:50 CDT 2016 |Updated: Tue Apr 19 09:58:35 CDT 2016 |Update: Clarified that the fixes for openssl_advisory18 cover the issue | described in this bulletin. The most recent version of this document is available here: http://aix.software.ibm.com/aix/efixes/security/openssl_advisory19.asc https://aix.software.ibm.com/aix/efixes/security/openssl_advisory19.asc ftp://aix.software.ibm.com/aix/efixes/security/openssl_advisory19.asc Security Bulletin: Vulnerability in OpenSSL affects AIX (CVE-2016-2842) =============================================================================== SUMMARY: This bulletin addresses CVE-2016-2842 for AIX. =============================================================================== VULNERABILITY DETAILS: OpenSSL vulnerabilities were disclosed on March 1, 2016 by the OpenSSL Project. OpenSSL is used by AIX. AIX addressed the applicable CVEs with the details provided in: Multiple vulnerabilities in OpenSSL affect AIX https://aix.software.ibm.com/aix/efixes/security/openssl_advisory18.asc An additional CVE, CVE-2016-2842, was also fixed but was not initially included in the March 1, 2016 OpenSSL Project announcement or in the associated security bulletin for this product. This bulletin only addresses CVE-2016-2842. Please see the bulletin linked above for the other CVEs that were addressed by the March 1, 2016 OpenSSL Project. CVEID: CVE-2016-2842 DESCRIPTION: OpenSSL is vulnerable to a denial of service, caused by the failure to verify that a certain memory allocation succeeds by the doapr_outch function. A remote attacker could exploit this vulnerability using a specially crafted string to cause an out-of-bounds write or consume an overly large amount of resources. CVSS Base Score: 7.5 CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/111304 for the current score CVSS Environmental Score*: Undefined CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) AFFECTED PRODUCTS AND VERSIONS: AIX 5.3, 6.1, 7.1, 7.2 VIOS 2.2.x The following fileset levels are vulnerable: key_fileset = osrcaix Fileset Lower Level Upper Level KEY -------------------------------------------------- openssl.base 0.9.8.401 0.9.8.2506 key_w_fs openssl.base 1.0.1.500 1.0.1.515 key_w_fs openssl.base 1.0.2.500 1.0.2.500 key_w_fs openssl.base 12.9.8.1100 12.9.8.2506 key_w_fs Note: to find out whether the affected filesets are installed on your systems, refer to the lslpp command found in AIX user's guide. Example: lslpp -L | grep -i openssl.base REMEDIATION: A. FIXES Fixes are available. | Please note that these fixes are the same as provided in | openssl_advisory18. The fixes for openssl_advisory18 also cover | the CVE described in this bulletin, CVE-2016-2842. The fixes can be downloaded via ftp or http from: ftp://aix.software.ibm.com/aix/efixes/security/openssl_fix18.tar http://aix.software.ibm.com/aix/efixes/security/openssl_fix18.tar https://aix.software.ibm.com/aix/efixes/security/openssl_fix18.tar The link above is to a tar file containing this signed advisory, fix packages, and OpenSSL signatures for each package. The fixes below include prerequisite checking. This will enforce the correct mapping between the fixes and AIX Technology Levels. Note that the tar file contains Interim fixes that are based on OpenSSL version, and AIX OpenSSL fixes are cumulative. AIX Level Interim Fix (*.Z) Fileset Name(prereq for installation) KEY -------------------------------------------------------------------------------------------- 5.3, 6.1, 7.1, 7.2 IV83169m9b.160401.epkg.Z openssl.base(0.9.8.2506) key_w_fix 5.3, 6.1, 7.1, 7.2 IV83169m9a.160401.epkg.Z openssl.base(1.0.1.515) key_w_fix 5.3, 6.1, 7.1, 7.2 IV83169s9d.160401.epkg.Z openssl.base(1.0.2.500) key_w_fix 5.3, 6.1, 7.1, 7.2 IV83169m9c.160401.epkg.Z openssl.base(12.9.8.2506) key_w_fix VIOS Level Interim Fix (*.Z) Fileset Name(prereq for installation) KEY -------------------------------------------------------------------------------------------- 2.2.* IV83169m9b.160401.epkg.Z openssl.base(0.9.8.2506) key_w_fix 2.2.* IV83169m9a.160401.epkg.Z openssl.base(1.0.1.515) key_w_fix 2.2.* IV83169s9d.160401.epkg.Z openssl.base(1.0.2.500) key_w_fix 2.2.* IV83169m9c.160401.epkg.Z openssl.base(12.9.8.2506) key_w_fix IBM recommends that the same certificate should ONLY be shared with identical server configuration and software. If the same certificate were shared with different server(s) configuration or software, IBM recommends replacing the different server(s) with unique certificates to protect against the DROWN exposure. To extract the fixes from the tar file: tar xvf openssl_fix18.tar cd openssl_fix18 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 ------------------------------------------------------------------------------------------------------ a5c629e778b9917e4d29edd996021a62874dcdc978d30cd56fb65395739d7f5a IV83169m9b.160401.epkg.Z key_w_csum 21dd42076309599682c56a92e1fceca793b6d7bb26bffd4b30d9aea9a429e26a IV83169m9a.160401.epkg.Z key_w_csum 7613b557bec19e1472a6e321ddff20d0026fee4c81097a81346a48f119347d67 IV83169s9d.160401.epkg.Z key_w_csum 14c8c21387f19eea212a964448a2ef1a0ecd1c8fb53f013b1035262d8aa6f831 IV83169m9c.160401.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 Published advisory OpenSSL signature file location: http://aix.software.ibm.com/aix/efixes/security/openssl_advisory19.asc.sig https://aix.software.ibm.com/aix/efixes/security/openssl_advisory19.asc.sig ftp://aix.software.ibm.com/aix/efixes/security/openssl_advisory19.asc.sig B. 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. WORKAROUNDS AND MITIGATIONS: None. =============================================================================== CONTACT US: Note: Keywords labeled as KEY in this document are used for parsing purposes. If you would like to receive AIX Security Advisories via email, please visit "My Notifications": http://www.ibm.com/support/mynotifications 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_pubkey.txt To obtain the PGP public key that can be used to communicate securely with the AIX Security Team via security-alert@austin.ibm.com you can either: A. Download the key from our web page: http://www.ibm.com/systems/resources/systems_p_os_aix_security_pgppubkey.txt 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. REFERENCES: Complete CVSS v3 Guide: http://www.first.org/cvss/user-guide On-line Calculator v3: http://www.first.org/cvss/calculator/3.0 ACKNOWLEDGEMENTS: None. CHANGE HISTORY: First Issued: Mon Apr 18 10:40:50 CDT 2016 | Updated: Tue Apr 19 09:58:35 CDT 2016 | Update: Clarified that the fixes for openssl_advisory18 cover the issue | described in this bulletin. =============================================================================== *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 Security Bulletin. Disclaimer 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.