7.5 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.1 High
AI Score
Confidence
High
0.002 Low
EPSS
Percentile
51.9%
IBM SECURITY ADVISORY
First Issued: Mon Dec 18 09:19:46 CST 2023
The most recent version of this document is available here:
https://aix.software.ibm.com/aix/efixes/security/bind_advisory25.asc
Security Bulletin: AIX is vulnerable to denial of service due to ISC BIND
(CVE-2023-3341)
===============================================================================
SUMMARY:
A vulnerability in ISC BIND could allow a remote attacker to cause a
denial of service (CVE-2023-3341) AIX uses ISC BIND as part of its DNS
functions.
===============================================================================
VULNERABILITY DETAILS:
CVEID: CVE-2023-3341
https://vulners.com/cve/CVE-2023-3341
DESCRIPTION: ISC BIND is vulnerable to a denial of service, caused by a
stack exhaustion flaw in control channel code. By sending a specially
crafted message over the control channel, a remote attacker could
exploit this vulnerability to cause named to terminate.
CVSS Base Score: 7.5
CVSS Temporal Score: See
https://exchange.xforce.ibmcloud.com/vulnerabilities/266515
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:H)
AFFECTED PRODUCTS AND VERSIONS:
AIX 7.2, 7.3
VIOS 3.1, 4.1
The following fileset levels are vulnerable:
key_fileset = aix
Fileset Lower Level Upper Level KEY
----------------------------------------------------------
bos.net.tcp.bind 7.2.5.100 7.2.5.101 key_w_fs
bos.net.tcp.bind 7.2.5.200 7.2.5.200 key_w_fs
bind.rte 7.1.916.0 7.1.916.2603 key_w_fs
bind.rte 7.3.916.0 7.3.916.2600 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.bind
REMEDIATION:
A. APARS
IBM has assigned the following APARs to this problem:
AIX Level APAR Availability SP KEY
-----------------------------------------------------
7.2.5 IJ49093 ** SP08 key_w_apar
VIOS Level APAR Availability SP KEY
-----------------------------------------------------
3.1.3 IJ49094 ** N/A key_w_apar
3.1.4 IJ49093 ** 3.1.4.40 key_w_apar
Subscribe to the APARs here:
https://www.ibm.com/support/pages/apar/IJ49093
https://www.ibm.com/support/pages/apar/IJ49094
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
IBM strongly recommends addressing the vulnerability now.
For bind.rte on 7.3 and if installed on 7.2 TL5, remediation is
a new fileset that is available for download from:
https://www.ibm.com/resources/mrs/assets?source=aixbp
AIX and VIOS iFixes are available for AIX 7.2 TL5 and VIO 3.1.
The fixes are cumulative and address previously issued AIX/VIOS
BIND security bulletins with respect to SP and TL.
The AIX and VIOS fixes can be downloaded via https from:
https://aix.software.ibm.com/aix/efixes/security/bind_fix25.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
---------------------------------------------
7.2.5.5 IJ44424s5.221129.epkg.Z key_w_fix
7.2.5.5 IJ49093s7.231109.epkg.Z key_w_fix
7.2.5.6 IJ49093s7.231109.epkg.Z key_w_fix
7.2.5.7 IJ49093s7.231109.epkg.Z key_w_fix
Please note that the above table refers to AIX TL/SP level as
opposed to fileset level, i.e., 7.2.5.6 is AIX 7200-05-06.
Note: Two iFixes are provided for AIX 7.2 TL5 SP5 and required if
the relevant filesets are installed.
IJ44424s5 is for the bos.net.tcp.bind_utils fileset.
IJ49093s7 is for the bos.net.tcp.bind fileset.
Please reference the Affected Products and Version section above
for help with checking installed fileset levels.
VIOS Level Interim Fix (*.Z) KEY
----------------------------------------------
3.1.3.21 IJ44424s5.221129.epkg.Z key_w_fix
3.1.3.21 IJ49094s4.231110.epkg.Z key_w_fix
3.1.3.30 IJ44424s5.221129.epkg.Z key_w_fix
3.1.3.30 IJ49094s4.231110.epkg.Z key_w_fix
3.1.3.40 IJ49094s4.231110.epkg.Z key_w_fix
3.1.4.10 IJ44424s5.221129.epkg.Z key_w_fix
3.1.4.10 IJ49093s7.231109.epkg.Z key_w_fix
3.1.4.21 IJ49093s7.231109.epkg.Z key_w_fix
3.1.4.31 IJ49093s7.231109.epkg.Z key_w_fix
Note: Two iFixes are provided for:
VIOS 3.1.3.21, 3.1.3.30
VIOS 3.1.4.10
Both iFixes are required if the relevant filesets are installed.
IJ44424s5 is for the bos.net.tcp.bind_utils fileset.
IJ49093s7 is for the bos.net.tcp.bind fileset.
To extract the fixes from the tar file:
tar xvf bind_fix25.tar
cd bind_fix25
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
-----------------------------------------------------------------------------------------------------
af0073ada814a0d8bbf219761175c8e889c8a1422cb5a5f37b6ca47192cca91b IJ44424s5.221129.epkg.Z key_w_csum
7c7f99d2df4876f43d0868b4deda27df7bcdcb89d61ce5282f593001ae845c0e IJ49093s7.231109.epkg.Z key_w_csum
1cb19ec13c7ce95a402be4ac2a63cc27dbcf395468a17d73c6d33fdfb645464b IJ49094s4.231110.epkg.Z key_w_csum
a773584176f0467a241a06e69764f0b74fe018c75f48ffaf0359c30464dd038f IJ49095s6.231110.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:
https://aix.software.ibm.com/aix/efixes/security/bind_advisory25.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:
https://www.ibm.com/support/pages/managing-interim-fixes-aix
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":
https://www.ibm.com/support/mynotifications
Contact IBM Support for questions related to this announcement:
https://ibm.com/support/
For information on how to securely verify AIX security bulletins and fixes:
https://www.ibm.com/support/pages/node/6985269
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
https://aix.software.ibm.com/aix/efixes/security/systems_p_os_aix_security_pubkey.txt
To verify the AIX/VIOS security bulletin:
Published advisory OpenSSL signature file location:
https://aix.software.ibm.com/aix/efixes/security/bind_advisory25.asc.sig
openssl dgst -sha256 -verify [pubkey_file] -signature [advisory_file].sig [advisory_file]
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: AIX is vulnerable to denial of service due to ISC BIND
(CVE-2023-3341)
https://www.ibm.com/support/pages/node/7099313
ACKNOWLEDGEMENTS:
None.
CHANGE HISTORY:
First Issued: Mon Dec 18 09:19:46 CST 2023
===============================================================================
*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.
7.5 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.1 High
AI Score
Confidence
High
0.002 Low
EPSS
Percentile
51.9%