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
    [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>

    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:

    [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_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:

        [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

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: https://vulners.com/cve/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.