5.3 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
LOW
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
5 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
0.003 Low
EPSS
Percentile
71.1%
IBM SECURITY ADVISORY
First Issued: Tue Mar 1 08:41:32 CST 2022
|Updated: Wed Mar 16 11:31:17 CDT 2022
|Update: New iFixes provided for all AIX and VIOS levels.
| The previous iFixes were not cumulative, and the new iFixes are
| intended to supplant the previous fixes.
The most recent version of this document is available here:
http://aix.software.ibm.com/aix/efixes/security/bind_advisory20.asc
https://aix.software.ibm.com/aix/efixes/security/bind_advisory20.asc
ftp://aix.software.ibm.com/aix/efixes/security/bind_advisory20.asc
Security Bulletin: Vulnerability in BIND affects AIX (CVE-2021-25219)
===============================================================================
SUMMARY:
There is a vulnerability in BIND that affects AIX.
===============================================================================
VULNERABILITY DETAILS:
CVEID: CVE-2021-25219
https://vulners.com/cve/CVE-2021-25219
https://vulners.com/cve/CVE-2021-25219
DESCRIPTION: ISC BIND is vulnerable to a denial of service, caused by a
flaw in response processing. By abusing a lame cache, an attacker
could exploit this vulnerability to cause a named resolver to spend
most of its CPU time on managing and checking the lame cache and
severely degrade resolver performance.
CVSS Base Score: 5.3
CVSS Temporal Score: See
https://exchange.xforce.ibmcloud.com/vulnerabilities/212375
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:L)
AFFECTED PRODUCTS AND VERSIONS:
AIX 7.1, 7.2, 7.3
VIOS 3.1
The following fileset levels are vulnerable:
key_fileset = aix
Fileset Lower Level Upper Level KEY
---------------------------------------------------------
bos.net.tcp.server 7.1.5.0 7.1.5.35 key_w_fs
bos.net.tcp.client 7.1.5.0 7.1.5.40 key_w_fs
bos.net.tcp.bind 7.2.4.0 7.2.4.1 key_w_fs
bos.net.tcp.bind_utils 7.2.4.0 7.2.4.3 key_w_fs
bos.net.tcp.bind 7.2.5.0 7.2.5.1 key_w_fs
bos.net.tcp.bind_utils 7.2.5.0 7.2.5.2 key_w_fs
bos.net.tcp.bind 7.2.5.100 7.2.5.100 key_w_fs
bos.net.tcp.bind_utils 7.2.5.100 7.2.5.100 key_w_fs
bos.net.tcp.bind 7.3.0.0 7.3.0.0 key_w_fs
bos.net.tcp.bind_utils 7.3.0.0 7.3.0.0 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.net.tcp.server
REMEDIATION:
A. APARS
IBM has assigned the following APARs to this problem:
AIX Level APAR Availability SP KEY
-----------------------------------------------------
7.1.5 IJ37222 ** SP10 key_w_apar
7.2.4 IJ37225 ** SP06 key_w_apar
7.2.5 IJ37223 ** SP04 key_w_apar
7.3.0 IJ37226 ** SP02 key_w_apar
VIOS Level APAR Availability SP KEY
-----------------------------------------------------
3.1.1 IJ37225 ** 3.1.1.60 key_w_apar
3.1.2 IJ37224 ** 3.1.2.40 key_w_apar
3.1.3 IJ37223 ** 3.1.3.20 key_w_apar
Subscribe to the APARs here:
http://www.ibm.com/support/pages/apar/IJ37222
http://www.ibm.com/support/pages/apar/IJ37223
http://www.ibm.com/support/pages/apar/IJ37224
http://www.ibm.com/support/pages/apar/IJ37225
http://www.ibm.com/support/pages/apar/IJ37226
https://www.ibm.com/support/pages/apar/IJ37222
https://www.ibm.com/support/pages/apar/IJ37223
https://www.ibm.com/support/pages/apar/IJ37224
https://www.ibm.com/support/pages/apar/IJ37225
https://www.ibm.com/support/pages/apar/IJ37226
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 and VIOS fixes are available.
The AIX and VIOS fixes can be downloaded via ftp or http from:
ftp://aix.software.ibm.com/aix/efixes/security/bind_fix20.tar
http://aix.software.ibm.com/aix/efixes/security/bind_fix20.tar
https://aix.software.ibm.com/aix/efixes/security/bind_fix20.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
----------------------------------------------
| 7.1.5.7 IJ37222m9c.220315.epkg.Z key_w_fix
| 7.1.5.8 IJ37222m9c.220315.epkg.Z key_w_fix
| 7.1.5.9 IJ37222m9c.220315.epkg.Z key_w_fix
| 7.2.4.3 IJ37225m5c.220315.epkg.Z key_w_fix
| 7.2.4.4 IJ37225m5c.220315.epkg.Z key_w_fix
| 7.2.4.5 IJ37225m5c.220315.epkg.Z key_w_fix
| 7.2.5.1 IJ37224m3c.220315.epkg.Z key_w_fix
| 7.2.5.2 IJ37224m3c.220315.epkg.Z key_w_fix
| 7.2.5.3 IJ37224m3c.220315.epkg.Z key_w_fix
| 7.3.0.1 IJ37226s1b.220315.epkg.Z key_w_fix
Please note that the above table refers to AIX TL/SP level as
opposed to fileset level, i.e., 7.2.5.2 is AIX 7200-05-02.
Please reference the Affected Products and Version section above
for help with checking installed fileset levels.
VIOS Level Interim Fix (*.Z) KEY
-----------------------------------------------
| 3.1.1.30 IJ37225m5c.220315.epkg.Z key_w_fix
| 3.1.1.40 IJ37225m5c.220315.epkg.Z key_w_fix
| 3.1.1.50 IJ37225m5c.220315.epkg.Z key_w_fix
| 3.1.2.10 IJ37224m3c.220315.epkg.Z key_w_fix
| 3.1.2.21 IJ37224m3c.220315.epkg.Z key_w_fix
| 3.1.3.10 IJ37224m3c.220315.epkg.Z key_w_fix
| 3.1.3.14 IJ37224m3c.220315.epkg.Z key_w_fix
The above fixes are cumulative and address previously issued
AIX/VIOS BIND security bulletins.
To extract the fixes from the tar file:
tar xvf bind_fix20.tar
cd bind_fix20
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
-----------------------------------------------------------------------------------------------------
| c97ca6a6f08834de85adf24854956cb23cc948b5fab83b87ed9314b49fedb97d IJ37222m9c.220315.epkg.Z key_w_csum
| 1b664c2db58503d69141d34e5b11165ce110d7b5150b228c9cd4ba6172094042 IJ37224m3c.220315.epkg.Z key_w_csum
| d0af2eab502a4ed848326db6d4af6680ad4fa015225cea58aacc807b8ff3b0f8 IJ37225m5c.220315.epkg.Z key_w_csum
| 6dab0239b497eab26d75a2b8cf5715b9d4c74cb10a1ae835b229dbf5037c12c0 IJ37226s1b.220315.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/bind_advisory20.asc.sig
https://aix.software.ibm.com/aix/efixes/security/bind_advisory20.asc.sig
ftp://aix.software.ibm.com/aix/efixes/security/bind_advisory20.asc.sig
C. FIX AND INTERIM FIX INSTALLATION
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/
Security Bulletin: Vulnerability in BIND affects AIX (CVE-2021-25219)
https://www.ibm.com/support/pages/node/6560382
ACKNOWLEDGEMENTS:
None.
CHANGE HISTORY:
First Issued: Tue Mar 1 08:41:32 CST 2022
| Updated: Wed Mar 16 11:31:17 CDT 2022
| Update: New iFixes provided for all AIX and VIOS levels.
| The previous iFixes were not cumulative, and the new iFixes are
| intended to supplant the previous fixes.
===============================================================================
*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.
5.3 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
LOW
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
5 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
0.003 Low
EPSS
Percentile
71.1%