IBM SECURITY ADVISORY First Issued: Wed Mar 2 08:43:07 CST 2016 The most recent version of this document is available here: http://aix.software.ibm.com/aix/efixes/security/openssl_advisory17.asc https://aix.software.ibm.com/aix/efixes/security/openssl_advisory17.asc ftp://aix.software.ibm.com/aix/efixes/security/openssl_advisory17.asc Security Bulletin: Vulnerabilities in OpenSSL affect AIX CVE-2015-3197 CVE-2015-4000 =============================================================================== SUMMARY: OpenSSL vulnerabilities were disclosed on January 28, 2016 by the OpenSSL Project. OpenSSL is used by AIX. AIX has addressed the applicable CVEs. =============================================================================== VULNERABILITY DETAILS: CVEID: CVE-2015-3197 DESCRIPTION: A malicious client can negotiate SSLv2 ciphers that have been disabled on the server and complete SSLv2 handshakes even if all SSLv2 ciphers have been disabled, provided that the SSLv2 protocol was not disabled via SSL_OP_NO_SSLv2. CVSS Base Score: 5.4 CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/110235 for the current score CVSS Environmental Score*: Undefined CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N) CVEID: CVE-2015-4000 DESCRIPTION: A previously published vulnerability in the TLS protocol allows a man-in-the-middle attacker to downgrade vulnerable TLS connections using ephemeral Diffie-Hellman key exchange to 512-bit export-grade cryptography. This vulnerability is known as 'Logjam'. AIX OpenSSL had the Logjam mitigation for TLS clients by rejecting handshakes with DH parameters shorter than 768 bits. This limit has now been increased to 1024 bits. CVSS Base Score: 4.3 CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/103294 for the current score CVSS Environmental Score*: Undefined CVSS Vector: (AV:N/AC:M/Au:N/C:N/I:P/A:N) 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 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. The fixes can be downloaded via ftp or http from: ftp://aix.software.ibm.com/aix/efixes/security/openssl_fix17.tar http://aix.software.ibm.com/aix/efixes/security/openssl_fix17.tar https://aix.software.ibm.com/aix/efixes/security/openssl_fix17.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 IV81287m9b.160217.epkg.Z openssl.base(0.9.8.2506) key_w_fix 5.3, 6.1, 7.1, 7.2 IV81287m9a.160217.epkg.Z openssl.base(1.0.1.515) key_w_fix 5.3, 6.1, 7.1, 7.2 IV81287m9c.160217.epkg.Z openssl.base(12.9.8.2506) key_w_fix VIOS Level Interim Fix (*.Z) Fileset Name(prereq for installation) KEY -------------------------------------------------------------------------------------------- 2.2.* IV81287m9b.160217.epkg.Z openssl.base(0.9.8.2506) key_w_fix 2.2.* IV81287m9a.160217.epkg.Z openssl.base(1.0.1.515) key_w_fix 2.2.* IV81287m9c.160217.epkg.Z openssl.base(12.9.8.2506) key_w_fix To extract the fixes from the tar file: tar xvf openssl_fix17.tar cd openssl_fix17 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 ------------------------------------------------------------------------------------------------------ 55d799969cca782bd66f362cf5683d5106e86884a4519d69a2ce65d2ae6de274 IV81287m9b.160217.epkg.Z key_w_csum 09658192c5f10636a43201c245da652083770a6e98c83d0922032b6b8938eb97 IV81287m9a.160217.epkg.Z key_w_csum 00b632cb9c4433e40f35e9db148051ca01944d111006ee5c5b94d8f237909220 IV81287m9c.160217.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_advisory17.asc.sig https://aix.software.ibm.com/aix/efixes/security/openssl_advisory17.asc.sig ftp://aix.software.ibm.com/aix/efixes/security/openssl_advisory17.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 v2 Guide: http://www.first.org/cvss/v2/guide On-line Calculator v2: http://nvd.nist.gov/CVSS-v2-Calculator 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: Wed Mar 2 08:43:07 CST 2016 =============================================================================== *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.