Headline
CVE-2021-38996: Security Bulletin: Vulnerabilities in AIX CAA (CVE-2022-22350, CVE-2021-38996)
IBM AIX 7.1, 7.2, 7.3, and VIOS 3.1 could allow a non-privileged local user to exploit a vulnerability in the AIX kernel to cause a denial of service. IBM X-Force ID: 213076.
Security Bulletin
Summary
There are multiple vulnerabilities in AIX CAA.
Vulnerability Details
Affected Products and Versions
Affected Product(s)
Version(s)
AIX
7.1
AIX
7.2
AIX
7.3
VIOS
3.1
The vulnerabilities in the following filesets are being addressed:
Fileset
Lower Level
Upper Level
bos.cluster.rte
7.1.5.0
7.1.5.38
bos.cluster.rte
7.2.4.0
7.2.4.4
bos.cluster.rte
7.2.5.0
7.2.5.1
bos.cluster.rte
7.2.5.100
7.2.5.101
bos.cluster.rte
7.3.0.0
7.3.0.0
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.cluster.rte
Remediation/Fixes
A. APARS
IBM has assigned the following APARs to this problem:
AIX Level
APAR
SP
7.1.5
IJ37355
SP10
7.2.4
IJ37496
SP06
7.2.5
IJ36682
SP04
7.3.0
IJ36596
SP02
VIOS Level
APAR
SP
3.1.1
IJ37496
3.1.1.60
3.1.2
IJ37512
3.1.2.40
3.1.3
IJ36682
3.1.3.20
Subscribe to the APARs here:
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.
An LPAR system reboot is required to complete the iFix installation, or Live Update may be used on AIX 7.2 and 7.3 to avoid a reboot.
The AIX and VIOS fixes can be downloaded via ftp or http from:
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
7.1.5.7
IJ37355s7a.220228.epkg.Z
7.1.5.8
IJ37355s8a.220228.epkg.Z
7.1.5.9
IJ37355s9a.220228.epkg.Z
7.1.5.9
IJ37355s9b.220228.epkg.Z
7.2.4.3
IJ37496s3a.220228.epkg.Z
7.2.4.4
IJ37496s4a.220228.epkg.Z
7.2.4.5
IJ37496s5a.220228.epkg.Z
7.2.5.1
IJ37512s1a.220228.epkg.Z
7.2.5.2
IJ37512s2a.220228.epkg.Z
7.2.5.3
IJ36682s3a.220228.epkg.Z
7.2.5.3
IJ36682s3b.220228.epkg.Z
7.3.0.1
IJ36596s1a.220228.epkg.Z
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.
NOTE: Multiple iFixes are provided for AIX 7100-05-09 and 7200-05-03.
IJ37355s9a is for AIX 7100-05-09 with bos.cluster.rte fileset level 7.1.5.38.
IJ37355s9b is for AIX 7100-05-09 with bos.cluster.rte fileset level 7.1.5.37.
IJ36682s3a is for AIX 7200-05-03 with bos.cluster.rte fileset level 7.2.5.101.
IJ36682s3b is for AIX 7200-05-03 with bos.cluster.rte fileset level 7.2.5.100.
Please reference the Affected Products and Version section above for help with checking installed fileset levels.
VIOS Level
Interim Fix
3.1.1.30
IJ37496s3a.220228.epkg.Z
3.1.1.40
IJ37496s4a.220228.epkg.Z
3.1.1.50
IJ37496s5a.220228.epkg.Z
3.1.2.10
IJ37512s1a.220228.epkg.Z
3.1.2.21
IJ37512s2a.220228.epkg.Z
3.1.3.10
IJ36682s3b.220228.epkg.Z
3.1.3.14
IJ36682s3a.220228.epkg.Z
To extract the fixes from the tar file:
tar xvf caa_fix2.tar
cd caa_fix2
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
6e45651c382f9915771c9714b994d26a783a8caecb8e3c8b3350d981aee7349b
IJ36596s1a.220228.epkg.Z
88a2f0bcc4b7676eab0db362fd885d360ad3a38104edbe7bed1e4c79a56be30d
IJ36682s3a.220228.epkg.Z
a81847ca47786818db8dce79f4a982c285815f561e2c9e8630840c229a27d381
IJ36682s3b.220228.epkg.Z
b4efa8234dc00c91148c75ec25e1c5fd3cd96ec691131ece6e458e5c33591335
IJ37355s7a.220228.epkg.Z
e141352471d842585e176bfb3ccc27289620b63de96478cca7688f4851841023
IJ37355s8a.220228.epkg.Z
9440584798abfa576e4e90287847f22cc9019281a213f1d289df330e75e77b56
IJ37355s9a.220228.epkg.Z
4d77a4e7fd8cd356deda29d6ff9a5996912ebd22e0898ede34725220d8df2577
IJ37355s9b.220228.epkg.Z
991ac1e17a4dd3b20feb44162b3f04a9dcda8cb2acce398e09c520b5871ccff3
IJ37496s3a.220228.epkg.Z
a0a24034a8a2fc3f2fa4ed8e5b05da045587300708812fe5c796a41b87b8e855
IJ37496s4a.220228.epkg.Z
2f74bee159291cec6944f8b522dbbf086f01b65a30da76595773b5851008c0ba
IJ37496s5a.220228.epkg.Z
95086a37dbf91e218f145c172cf2ca39029dfbecb00f072d4a36887f91536551
IJ37512s1a.220228.epkg.Z
9e2ecbbe30354bdd275679ac9e22ec7ca0dfb8a87cbe73f46767422b90206afd
IJ37512s2a.220228.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:
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 and 7.3 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:
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
References
Off
Change History
01 Mar 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.
Document Location
Worldwide
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