IBM SECURITY ADVISORY First Issued: Tue Nov 7 11:16:49 CST 2023 The most recent version of this document is available here: https://aix.software.ibm.com/aix/efixes/security/python_advisory6.asc Security Bulletin: AIX is affected by a denial of service (CVE-2023-45167) and a security restrictions bypass (CVE-2023-40217) due to Python =============================================================================== SUMMARY: A vulnerability in Python could allow a non-privileged local user to cause a denial of service (CVE-2023-45167) and a remote attacker to cause a security restrictions bypass (CVE-2023-40217). Python is used by AIX as part of Ansible node management automation. =============================================================================== VULNERABILITY DETAILS: CVEID: CVE-2023-45167 https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-45167 DESCRIPTION: IBM AIX's Python implementation could allow a non-privileged local user to exploit a vulnerability to cause a denial of service. CVSS Base Score: 6.2 CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/267965 for the current score CVSS Environmental Score*: Undefined CVSS Vector:(CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) CVEID: CVE-2023-40217 https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-40217 DESCRIPTION: Python could allow a remote attacker to bypass security restrictions, caused by a race condition in the SSLSocket module. When the socket is closed before the TLS handshake is complete, the data is treated as if it had been encrypted by TLS. An attacker could exploit this vulnerability to bypass the TLS handshake and inject a malicious client certificate into the connection and gain access to the server's resources without being authenticated. CVSS Base Score: 7.4 CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/264374 for the current score CVSS Environmental Score*: Undefined CVSS Vector:(CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N) AFFECTED PRODUCTS AND VERSIONS: AIX 7.3 VIOS 4.1 The following fileset levels are vulnerable: key_fileset = osrcaix Fileset Lower Level Upper Level KEY ------------------------------------------------------ python3.9.base 3.9.0.0 3.9.17.1 key_w_fs Note: A. Latest level of Python fileset is available from the web download site: https://www.ibm.com/resources/mrs/assets?source=aixbp 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 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 To extract the fixes from the tar file: zcat python-3.9.18.0.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_advisory6.asc.sig 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": http://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/python_advisory6.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: https://www.first.org/cvss/user-guide On-line Calculator v3: https://www.first.org/cvss/calculator/3.0 RELATED INFORMATION: Security Bulletin: AIX is affected by a denial of service (CVE-2023-45167) and a security restrictions bypass (CVE-2023-40217) due to Python https://www.ibm.com/support/pages/node/7068084 ACKNOWLEDGEMENTS: None. CHANGE HISTORY: First Issued: Tue Nov 7 11:16:49 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.