IBM SECURITY ADVISORY First Issued: Wed Dec 20 12:50:52 CST 2023 The most recent version of this document is available here: https://aix.software.ibm.com/aix/efixes/security/smbcd_advisory3.asc Security Bulletin: AIX is vulnerable to a denial of service due to the AIX SMB client (CVE-2023-45165) =============================================================================== SUMMARY: A vulnerability in the AIX SMB client daemon could allow a non-privileged local user to cause a denial of service (CVE-2023-45165). AIX uses the SMB client daemon to access files on SMB servers. =============================================================================== VULNERABILITY DETAILS: CVEID: CVE-2023-45165 https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-45165 DESCRIPTION: IBM AIX could allow a non-privileged local user to exploit a vulnerability in the AIX SMB client to cause a denial of service. CVSS Base Score: 6.2 CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/267963 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) AFFECTED PRODUCTS AND VERSIONS: AIX 7.2, 7.3 The following fileset levels are vulnerable: key_fileset = osrcaix Fileset Lower Level Upper Level KEY ------------------------------------------------------------- smbc.rte 7.2.0.0 7.2.302.10 key_w_fs To determine if your system is vulnerable, execute the following commands: lslpp -L | grep -i smbc.rte REMEDIATION: FIXES IBM strongly recommends addressing the vulnerability now. The latest SMB client fileset may be downloaded from: https://www.ibm.com/resources/mrs/assets?source=aixbp To extract the fixes from the tar file: For AIX 7.2 and 7.3 TL0: gunzip smbc_302_fileset_72.tar.gz | tar xvf For AIX 7.3 TL1: gunzip smbc_302_fileset_73.tar.gz | 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. To preview the fix installation: installp -apYd . smbc To install the fix package: installp -aXYd . smbc 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 security bulletin: Published advisory OpenSSL signature file location: https://aix.software.ibm.com/aix/efixes/security/smbcd_advisory3.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 vulnerable to a denial of service due to the AIX SMB client (CVE-2023-45165) https://www.ibm.com/support/pages/node/7100970 ACKNOWLEDGEMENTS: None. CHANGE HISTORY: First Issued: Wed Dec 20 12:50:52 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.