Security Bulletin
Summary
UPDATED May 17 (Corrected the affected fileset levels for AIX 7.2 TL5 and removed bos.net.tcp.bind 7.2.5.200.): A vulnerability in ISC BIND could allow a remote attacker to cause a denial of service (CVE-2022-38178, CVE-2022-3080, CVE-2022-38177, CVE-2022-2795). AIX uses ISC BIND as part of its DNS functions.
Vulnerability Details
CVEID: CVE-2022-38178
DESCRIPTION: ISC BIND is vulnerable to a denial of service, caused by a memory leak in the DNSSEC verification code for the EdDSA algorithm. By spoofing the target resolver with responses that have a malformed EdDSA signature, a remote attacker could exploit this vulnerability to cause named to crash.
CVSS Base score: 7.5
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/236706 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
CVEID: CVE-2022-3080
DESCRIPTION: ISC BIND is vulnerable to a denial of service, caused by an error when stale cache and stale answers are enabled, option stale-answer-client-timeout is set to 0 and there is a stale CNAME in the cache for an incoming query. By sending a specially-crafted request, a remote attacker could exploit this vulnerability to cause named to crash.
CVSS Base score: 7.5
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/236704 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
CVEID: CVE-2022-38177
DESCRIPTION: ISC BIND is vulnerable to a denial of service, caused by a small memory leak in the DNSSEC verification code for the ECDSA algorithm. By spoofing the target resolver with responses that have a malformed ECDSA signature, a remote attacker could exploit this vulnerability to cause named to crash.
CVSS Base score: 7.5
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/236705 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
CVEID: CVE-2022-2795
DESCRIPTION: ISC BIND is vulnerable to a denial of service, caused by a flaw in resolver code. By flooding the target resolver with queries, a remote attacker could exploit this vulnerability to severely degrade the resolver's performance, effectively denying legitimate clients access to the DNS resolution service.
CVSS Base score: 5.3
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/236701 for the current score.
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
| Affected Product(s) | Version(s) |
| AIX | 7.1 |
| AIX | 7.2 |
| AIX | 7.3 |
| VIOS | 3.1 |
The following fileset levels are vulnerable:
| Fileset | Lower Level | Upper Level |
| bos.net.tcp.server | 7.1.5.0 | 7.1.5.35 |
| bos.net.tcp.client | 7.1.5.0 | 7.1.5.42 |
| bos.net.tcp.bind_utils | 7.2.5.0 | 7.2.5.4 |
| bos.net.tcp.bind_utils | 7.2.5.100 | 7.2.5.102 |
| bos.net.tcp.bind_utils | 7.2.5.200 | 7.2.5.200 |
| bos.net.tcp.bind_utils | 7.3.0.0 | 7.3.0.2 |
| bind.rte | 7.1.916.0 | 7.1.916.2600 |
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/Fixes
A. APARS
IBM has assigned the following APARs to this problem:
| AIX Level | APAR | SP |
| 7.1.5 | IJ44422 | SP12 |
| 7.2.5 | IJ44425 | SP06 |
| 7.3.0 | IJ44427 | SP04 |
| 7.3.1 | IJ44426 | SP02 |
| VIOS Level | APAR | SP |
| 3.1.2 | IJ44423 | 3.1.2.60 |
| 3.1.3 | IJ44424 | 3.1.3.40 |
| 3.1.4 | IJ44425 | 3.1.4.20 |
Subscribe to the APARs here:
https://www.ibm.com/support/pages/apar/IJ44422
https://www.ibm.com/support/pages/apar/IJ44423
https://www.ibm.com/support/pages/apar/IJ44424
https://www.ibm.com/support/pages/apar/IJ44425
https://www.ibm.com/support/pages/apar/IJ44426
https://www.ibm.com/support/pages/apar/IJ44427
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.
AIX and VIOS fixes are available. 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_fix22.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 |
| 7.1.5.8 | IJ44422mAa.221220.epkg.Z |
| 7.1.5.9 | IJ44422mAa.221220.epkg.Z |
| 7.1.5.10 | IJ44422mAa.221220.epkg.Z |
| 7.1.5.11 | IJ44422sBa.230317.epkg.Z |
| 7.2.5.3 | IJ44425m4b.230217.epkg.Z |
| 7.2.5.4 | IJ44425m4b.230217.epkg.Z |
| 7.2.5.5 | IJ44425s5b.230214.epkg.Z |
| 7.3.0.1 | IJ44427m2a.221220.epkg.Z |
| 7.3.0.2 | IJ44427m2a.221220.epkg.Z |
| 7.3.0.3 | IJ44427s3a.230317.epkg.Z |
Please note that the above table refers to AIX TL/SP level as opposed to fileset level, i.e., 7.2.5.4 is AIX 7200-05-04.
Please reference the Affected Products and Version section above for help with checking installed fileset levels.
| VIOS Level | Interim Fix |
| 3.1.2.21 | IJ44423m2b.230217.epkg.Z |
| 3.1.2.30 | IJ44423m2b.230217.epkg.Z |
| 3.1.2.40 | IJ44423m2b.230217.epkg.Z |
| 3.1.2.50 | IJ44423s5a.230404.epkg.Z |
| 3.1.3.10 | IJ44425m4b.230217.epkg.Z |
| 3.1.3.14 | IJ44425m4b.230217.epkg.Z |
| 3.1.3.21 | IJ44425m4b.230217.epkg.Z |
| 3.1.3.30 | IJ44424s3a.230404.epkg.Z |
| 3.1.4.10 | IJ44425s5b.230214.epkg.Z |
For bind.rte on 7.3 TL1 and if installed on 7.2 TL5:
| AIX Level | Interim Fix |
| 7.2.5 | IJ44426s2.221130.epkg.Z |
| 7.3.1 | IJ44426s2.221130.epkg.Z |
To extract the fixes from the tar file:
tar xvf bind_fix22.tar
cd bind_fix22
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 |
| d4c4f5597a935695bafffa5a9f31a17c694f003c0a01a3dc2d9d0ccfe06153a9 | IJ44422mAa.221220.epkg.Z |
| dc937745acdc4d7e3eec7ebd256f18bfce782ad1458eb439bf05e61367b2598d | IJ44422sBa.230317.epkg.Z |
| 70f95b035123da0b39350c88c57040725ee1f1421931be5354b5e4a56e446f96 | IJ44423m2b.230217.epkg.Z |
| 4dbd611880ec795916fdd80ee67c971d19d4887c3027a947cee787f44574b319 | IJ44423s5a.230404.epkg.Z |
| 50436dbd5b5cfa37efa361420af1638f1769a50011ee61e739990bb457f43952 | IJ44424s3a.230404.epkg.Z |
| 46f8fad10cb6bc6f611f9981f41992855702ec11725bb05379db77593459b7b3 | IJ44425m4b.230217.epkg.Z |
| 2245c6270194dddf66b5ba6dd7624921062910d07e6c80a61fdf82270489a3b3 | IJ44425s5b.230214.epkg.Z |
| 95bbb3346e950c4f920b30f016f2f6c60dbf87e27b9ae396a4c25dbd0e400573 | IJ44426s2.221130.epkg.Z |
| 648bd3bbedd6396f917de3deef892b04e3224c5ab40f9667ada4ef464698ccfb | IJ44427m2a.221220.epkg.Z |
| 64687c4d69d5ab4cc2c2bbe72f884bdc5dd0cf65a6d7cebf2f9f18cb877c973b | IJ44427s3a.230317.epkg.Z |
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_advisory22.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
Get Notified about Future Security Bulletins
References
Acknowledgement
Change History
17 May 2023: Corrected the affected fileset levels for AIX 7.2 TL5 and removed bos.net.tcp.bind 7.2.5.200.
5 Apr 2023: Corrected the affected upper fileset levels for AIX to show that AIX 7.1 TL5 SP11 and 7.3 TL0 SP03 are affected. Corrected the affected upper fileset levels for VIOS to show that VIOS 3.1.2.50 and 3.1.3.30 are affected. Added iFixes for AIX 7.1 TL5 SP11 and 7.3 TL0 SP03. Added iFixes for VIOS 3.1.2.50 and 3.1.3.30.
22 Feb 2023: New iFixes provided for AIX 7.2 TL5 and VIOS 3.1. The new iFixes are intended to replace the original iFixes due to a technical issue that could cause named to core dump.
28 Dec 2022: Added fileset information for AIX 7.2 TL5 SP5
22 Dec 2022: Initial Publication
*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. In addition to other efforts to address potential vulnerabilities, IBM periodically updates the record of components contained in our product offerings. As part of that effort, if IBM identifies previously unidentified packages in a product/service inventory, we address relevant vulnerabilities regardless of CVE date. Inclusion of an older CVEID does not demonstrate that the referenced product has been used by IBM since that date, nor that IBM was aware of a vulnerability as of that date. We are making clients aware of relevant vulnerabilities as we become aware of them. "Affected Products and Versions" referenced in IBM Security Bulletins are intended to be only products and versions that are supported by IBM and have not passed their end-of-support or warranty date. Thus, failure to reference unsupported or extended-support products and versions in this Security Bulletin does not constitute a determination by IBM that they are unaffected by the vulnerability. Reference to one or more unsupported versions in this Security Bulletin shall not create an obligation for IBM to provide fixes for any unsupported or extended-support products or versions.
Document Location
Worldwide
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Document Information
Modified date:
16 January 2024
UID
ibm16851445