CVE-2022-41290: Security Bulletin: AIX is affected by a root privilege escalation vulnerability (CVE-2022-41290)

Security Bulletin

Summary

A vulnerability in the AIX rm_mlcache_file user command could allow a non-privileged local user to obtain root privileges (CVE-2022-41290).

Vulnerability Details

CVEID: CVE-2022-41290
DESCRIPTION: IBM AIX could allow a non-privileged local user to exploit a vulnerability in the rm_mlcache_file command to obtain root privileges.
CVSS Base score: 8.4
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/236690 for the current score.
CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)

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.rte.install

7.1.5.0

7.1.5.48

bos.rte.install

7.2.5.0

7.2.5.5

bos.rte.install

7.2.5.100

7.2.5.105

bos.rte.install

7.3.0.0

7.3.0.3

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.rte.install

Remediation/Fixes

A. APARS

IBM has assigned the following APARs to this problem:

AIX Level

APAR

SP

7.1.5

IJ42230

SP11

7.2.5

IJ42163

SP05

7.3.0

IJ42234

SP03

VIOS Level

APAR

SP

3.1.2

IJ42232

3.1.2.50

3.1.3

IJ42163

3.1.3.30

Subscribe to the APARs here:

https://www.ibm.com/support/pages/apar/IJ42163

https://www.ibm.com/support/pages/apar/IJ42230

https://www.ibm.com/support/pages/apar/IJ42232

https://www.ibm.com/support/pages/apar/IJ42234

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.

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

ftp://aix.software.ibm.com/aix/efixes/security/rmmlcache_fix.tar

http://aix.software.ibm.com/aix/efixes/security/rmmlcache_fix.tar

https://aix.software.ibm.com/aix/efixes/security/rmmlcache_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

7.1.5.8

IJ42230mAa.221208.epkg.Z

7.1.5.9

IJ42230mAa.221208.epkg.Z

7.1.5.10

IJ42230mAa.221208.epkg.Z

7.2.5.3

IJ42163m4a.221213.epkg.Z

7.2.5.4

IJ42163m4a.221213.epkg.Z

7.3.0.1

IJ42234m2a.221213.epkg.Z

7.3.0.2

IJ42234m2a.221213.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

IJ42232m2a.221213.epkg.Z

3.1.2.30

IJ42232m2a.221213.epkg.Z

3.1.2.40

IJ42232m2a.221213.epkg.Z

3.1.3.10

IJ42163m4a.221213.epkg.Z

3.1.3.14

IJ42163m4a.221213.epkg.Z

3.1.3.21

IJ42163m4a.221213.epkg.Z

To extract the fixes from the tar file:

tar xvf rmmlcache_fix.tar

cd rmmlcache_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

151660fafedd0bf43da9579f272cf01fa4435ae6d58a118d9628a91f1dbdfc49

IJ42163m4a.221213.epkg.Z

09f08f7976bb940137be2cf67362481e1b9d892b8ab02e94464fdcbd4be49e00

IJ42230mAa.221208.epkg.Z

9ae3e496e4017b98ff10327ad03778c45e0402a8024c33f257754a8f2bf0aaf8

IJ42232m2a.221213.epkg.Z

8c3a1e7a9dbb76c005158184b88fffa07b16cf3f001565578f7690fb599d9a72

IJ42234m2a.221213.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:

http://aix.software.ibm.com/aix/efixes/security/rmmlcache_advisory.asc.sig

https://aix.software.ibm.com/aix/efixes/security/rmmlcache_advisory.asc.sig

ftp://aix.software.ibm.com/aix/efixes/security/rmmlcache_advisory.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

References

Off

Acknowledgement

Change History

14 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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