Security Bulletin: AIX is affected by multiple vulnerabilities due to Python (CVE-2023-52425, CVE-2023-52426, CVE-2023-6597)

Summary

Vulnerabilities in Python could allow a remote or local attacker to cause a denial of service (CVE-2023-52425, CVE-2023-52426) or launch further attacks on the system (CVE-2023-6597). Python is used by AIX as part of Ansible node management automation.

Vulnerability Details

CVEID:CVE-2023-52425
**DESCRIPTION:**libexpat is vulnerable to a denial of service, caused by improper system resource allocation. By sending a specially crafted request using an overly large token, a remote attacker could exploit this vulnerability to cause a denial of service.
CVSS Base score: 7.5
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/281438 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-2023-52426
**DESCRIPTION:**libexpat is vulnerable to a denial of service, caused by an XML entity expansion flaw if XML_DTD is undefined at compile time. By compiling specially crafted XML input, a local attacker could exploit this vulnerability to cause a denial of service.
CVSS Base score: 5.1
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/281439 for the current score.
CVSS Vector: (CVSS:3.0/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:CVE-2023-6597
**DESCRIPTION:**Python could provide weaker than expected security, caused by an issue with tempfile.TemporaryDirectory fails removing dir in some edge cases related to symlinks. A local attacker could exploit this vulnerability to launch further attacks on the system.
CVSS Base score: 8.4
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/283230 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

The following fileset levels are vulnerable:

Note:

A. Latest level of Python fileset is available from the web download site:

<https://www.ibm.com/resources/mrs/assets?source=aixbp&gt;

To find out whether the affected filesets are installed on your systems, refer to the lslpp command found in the AIX user’s guide.

Example: lslpp -L | grep -i python3.9.base

Remediation/Fixes

FIXES

IBM strongly recommends addressing the vulnerability now.

A fix is available, and it can be downloaded from:

<https://www.ibm.com/resources/mrs/assets?source=aixbp&gt;

To extract the fixes from the tar file:

zcat python-3.9.18.2.tar.Z | tar xvf -

IMPORTANT: If possible, it is recommended that a mksysb backup of the system be created. Verify it is both bootable and readable before proceeding.

Note that all the previously reported security vulnerability fixes are also included in above mentioned fileset level.

To preview the fix installation:

installp -apYd . python3.9.base

To install the fix package:

installp -aXYd . python3.9.base

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/python_advisory8.asc.sig&gt;

Workarounds and Mitigations

None