There is a vulnerability in the AIX trace facility.

IBM SECURITY ADVISORY

First Issued: Tue Jun 15 19:09:20 CDT 2021

The most recent version of this document is available here:
http://aix.software.ibm.com/aix/efixes/security/trace_advisory.asc
https://aix.software.ibm.com/aix/efixes/security/trace_advisory.asc
ftp://aix.software.ibm.com/aix/efixes/security/trace_advisory.asc

Security Bulletin: Vulnerability in the AIX trace facility (CVE-2021-29706)

===============================================================================

SUMMARY:

There is a vulnerability in the AIX trace facility.

===============================================================================

VULNERABILITY DETAILS:

CVEID: CVE-2021-29706
    https://vulners.com/cve/CVE-2021-29706
    https://vulners.com/cve/CVE-201-29706
DESCRIPTION: IBM AIX could allow a non-privileged local user to exploit a
    vulnerability in the trace facility to expose sensitive information
    or cause a denial of service.
CVSS Base Score: 6.8
CVSS Temporal Score: See 
    https://exchange.xforce.ibmcloud.com/vulnerabilities/200663
    for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H)


AFFECTED PRODUCTS AND VERSIONS:

    AIX 7.1

    The vulnerabilities in the following filesets are being addressed:
    
    key_fileset = aix

    Fileset                 Lower Level  Upper Level KEY 
    ---------------------------------------------------------
    bos.mp64                7.1.5.0      7.1.5.42    key_w_fs
    
    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 bos.mp64


REMEDIATION:

    A. APARS
        
        IBM has assigned the following APARs to this problem:

        AIX Level APAR     Availability  SP        KEY
        -----------------------------------------------------
        7.1.5     IJ32940  **            SP09      key_w_apar

        Subscribe to the APARs here:

        http://www.ibm.com/support/pages/apar/IJ32940

        https://www.ibm.com/support/pages/apar/IJ32940

        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

        AIX fixes are available.

        An LPAR system reboot is required to complete the iFix installation.

        The AIX fixes can be downloaded via ftp or http from:

        ftp://aix.software.ibm.com/aix/efixes/security/trace_fix.tar
        http://aix.software.ibm.com/aix/efixes/security/trace_fix.tar
        https://aix.software.ibm.com/aix/efixes/security/trace_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
        ----------------------------------------------
        7.1.5.6    IJ32940m6a.210615.epkg.Z  key_w_fix
        7.1.5.6    IJ32940m6b.210615.epkg.Z  key_w_fix
        7.1.5.7    IJ32940m7a.210615.epkg.Z  key_w_fix
        7.1.5.7    IJ32940m7b.210615.epkg.Z  key_w_fix
        7.1.5.8    IJ32940s8a.210615.epkg.Z  key_w_fix
        7.1.5.8    IJ32940s8b.210615.epkg.Z  key_w_fix

        Please note that the above table refers to AIX TL/SP level as
        opposed to fileset level, i.e., 7.1.5.7 is AIX 7100-05-07.

        NOTE:  Multiple iFixes are provided for AIX 7100-05-06,
        7100-05-07, and 7100-05-08.
        IJ32940m6a is for AIX 7100-05-06 with bos.mp64 fileset level 7.1.5.38.
        IJ32940m6b is for AIX 7100-05-06 with bos.mp64 fileset level 7.1.5.37.
        IJ32940m7a is for AIX 7100-05-07 with bos.mp64 fileset level 7.1.5.40.
        IJ32940m7b is for AIX 7100-05-07 with bos.mp64 fileset level 7.1.5.39.
        IJ32940s8a is for AIX 7100-05-08 with bos.mp64 fileset level 7.1.5.42.
        IJ32940s8b is for AIX 7100-05-08 with bos.mp64 fileset level 7.1.5.41.

        Please reference the Affected Products and Version section above
        for help with checking installed fileset levels.

        The fixes are cumulative and address previously issued
        AIX kernel security bulletins with respect to SP and TL,
        which includes:
        https://aix.software.ibm.com/aix/efixes/security/power9_advisory.asc
        https://www.ibm.com/support/pages/node/6370729
        https://aix.software.ibm.com/aix/efixes/security/gencore_advisory.asc
        https://www.ibm.com/support/pages/node/6406022 


        To extract the fixes from the tar file:

        tar xvf trace_fix.tar
        cd trace_fix

        Verify you have retrieved the fixes intact:

        The checksums below were generated using the
        "openssl dgst -sha256 [filename]" command as the following:

        openssl dgst -sha256                                              filename                 KEY
        -----------------------------------------------------------------------------------------------------
        8876568f9b7655b79a03737de3a9b43de54c93dc9ff8da34d82abc28be288ce8  IJ32940m6a.210615.epkg.Z key_w_csum
        5c56e2b9eb8338dc05ac9aefec8eaa3aaefa8be0f25a3b3171ebccd1d1f3a86b  IJ32940m6b.210615.epkg.Z key_w_csum
        1b46af7f440fb5ed0526a68a8d4ead487272893871859e8a85d852d656dcbb43  IJ32940m7a.210615.epkg.Z key_w_csum
        13d4ca34b088f2a939461cc7b99aae70240143d1760701283428b5a36da5a5b6  IJ32940m7b.210615.epkg.Z key_w_csum
        5650287a5fc28411b509d41ab852a2d5617ab7a9f3f23a4c07797bb717380960  IJ32940s8a.210615.epkg.Z key_w_csum
        7408d7ff31ada51fed41de9b483522f855f160cbda816ec792ac20262644b99b  IJ32940s8b.210615.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 Support at
        http://ibm.com/support/ and describe the discrepancy.         

        openssl dgst -sha256 -verify [pubkey_file] -signature [advisory_file].sig [advisory_file]

        openssl dgst -sha256 -verify [pubkey_file] -signature [ifix_file].sig [ifix_file]

        Published advisory OpenSSL signature file location:

        http://aix.software.ibm.com/aix/efixes/security/trace_advisory.asc.sig
        https://aix.software.ibm.com/aix/efixes/security/trace_advisory.asc.sig
        ftp://aix.software.ibm.com/aix/efixes/security/trace_advisory.asc.sig 

    C. FIX AND INTERIM FIX INSTALLATION

        An LPAR system reboot is required to complete the iFix installation,
        or Live Update may be used on AIX 7.2 to avoid a reboot.

        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

Contact IBM Support for questions related to this announcement:

    http://ibm.com/support/
    https://ibm.com/support/

To obtain the OpenSSL public key that can be used to verify the
signed advisories and ifixes:

    Download the key from our web page:

ftp://ftp.software.ibm.com/systems/power/AIX/systems_p_os_aix_security_pubkey.txt

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

RELATED INFORMATION:

IBM Secure Engineering Web Portal
    http://www.ibm.com/security/secure-engineering/bulletins.html

IBM Product Security Incident Response Blog
    https://www.ibm.com/blogs/psirt/

ACKNOWLEDGEMENTS:

None.

CHANGE HISTORY:

First Issued: Tue Jun 15 19:09:20 CDT 2021

===============================================================================

*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.