IBM SECURITY ADVISORY First Issued: Fri Aug 15 10:26:30 CDT 2014 Updated: Fri Aug 22 08:17:41 CDT 2014 Update: fixed APAR availability dates |Update: Mon Aug 25 15:18:37 CDT 2014 |Update Corrected a couple Service Pack level#s The most recent version of this document is available here: http://aix.software.ibm.com/aix/efixes/security/libxml2_advisory.asc https://aix.software.ibm.com/aix/efixes/security/libxml2_advisory.asc ftp://aix.software.ibm.com/aix/efixes/security/libxml2_advisory.asc =============================================================================== VULNERABILITY SUMMARY VULNERABILITY: AIX libxml2 vulnerability PLATFORMS: AIX 6.1 and 7.1 releases VIOS 2.2.* SOLUTION: Apply the fix as described below THREAT: A remote attacker could exploit this vulnerability using a specially-crafted XML document containing malicious attributes to consume all available CPU resources. CVE Number: CVE-2014-0191 CVSS=5.0 Reboot required? NO Workarounds? NO Protected by FPM? NO Protected by SED? NO =============================================================================== DETAILED INFORMATION I. DESCRIPTION Libxml2 is vulnerable to a denial of service, caused by the expansion of internal entities within the xmlParserHandlePEReference(). II. CVSS CVSS Base Score: 5 CVSS Temporal Score: See http://xforce.iss.net/xforce/xfdb/93092 for more information CVSS Environmental Score*: Undefined CVSS Vector: (AV:N/AC:L/Au:N/C:N/I:N/A:P) 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.rte.control The following fileset levels are vulnerable: AIX Fileset Lower Level Upper Level KEY -------------------------------------------------------- bos.rte.control 6.1.8.0 6.1.8.17 key_w_fix bos.rte.control 6.1.9.0 6.1.9.15 key_w_fix bos.rte.control 7.1.2.0 7.1.2.17 key_w_fix bos.rte.control 7.1.3.0 7.1.3.15 key_w_fix AIX Fileset (VIOS) Lower Level Upper Level ---------------------------------------------------------------- bos.rte.control 6.1.8.0(2.2.2.0) 6.1.8.17(2.2.2.4) bos.rte.control 6.1.9.0(2.2.3.0) 6.1.9.15(2.2.3.3) IV. SOLUTIONS A. APARS IBM has assigned the following APARs to this problem: AIX Level APAR number Availability KEY ------------------------------------------------------------ | 6.1.8 IV62447 12/31/2014 SP6 key_w_apar 6.1.9 IV62448 10/24/2014 SP4 key_w_apar | 7.1.2 IV62449 12/31/2014 SP6 key_w_apar 7.1.3 IV62450 10/24/2014 SP4 key_w_apar Subscribe to the APARs here: http://www.ibm.com/support/docview.wss?uid=isg1IV62447 http://www.ibm.com/support/docview.wss?uid=isg1IV62448 http://www.ibm.com/support/docview.wss?uid=isg1IV62449 http://www.ibm.com/support/docview.wss?uid=isg1IV62450 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/libxml2_fix.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. AIX Level Interim Fix (*.Z) KEY --------------------------------------------------- 6.1.8.4 IV62447s4a.140715.epkg.Z key_w_fix 6.1.9.3 IV62448s3a.140715.epkg.Z key_w_fix 7.1.2.4 IV62449s4a.140715.epkg.Z key_w_fix 7.1.3.3 IV62450s3a.140715.epkg.Z key_w_fix VIOS Level Interim Fix (*.Z) ------------------------------------- 2.2.2.4 IV62447s4a.140715.epkg.Z 2.2.3.3 IV62448s3a.140715.epkg.Z To extract the fixes from the tar file: tar xvf libxml2_fix.tar cd libxml2_fix Verify you have retrieved the fixes intact: The checksums below were generated using the "openssl dgst -sha256 file" command is the following: openssl dgst -sha256 filename KEY ---------------------------------------------------------------------------------------------------- c3b02f8faf29386056616d4ec015acc47d5b8849e84a6f10912db62082fd8a23 IV62447s4a.140715.epkg.Z key_w_csum d0beae655b28178f13952fb0da831e028a28b9ed25d3cfe267e61cbcf08ff5aa IV62448s3a.140715.epkg.Z key_w_csum 2ce78311783f31c76abc8fba4d8f4ebeb376c64e23c268f954b0b9356d431755 IV62449s4a.140715.epkg.Z key_w_csum 3b414db115af1f4d32879474d14d8aaed276f149db6bc022e398f2c58a6da0a2 IV62450s3a.140715.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/libxml2_advisory.asc.sig https://aix.software.ibm.com/aix/efixes/security/libxml2_advisory.asc.sig ftp://aix.software.ibm.com/aix/efixes/security/libxml2_advisory.asc.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. Ti 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; thus, IBM does not warrant the fully correct functionality of an interim fix. 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 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 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 request 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 IBM discovered and fixed this vulnerability as part of its commitment to secure the AIX operating system. 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/75510 CVE-2014-0191: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2014-0191 *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.