IBM SECURITY ADVISORY First Issued: Tue Jan 17 09:54:47 CST 2023 The most recent version of this document is available here: https://aix.software.ibm.com/aix/efixes/security/x11_advisory.asc Security Bulletin: AIX is vulnerable to a buffer overflow due to X11 (CVE-2022-47990) =============================================================================== SUMMARY: A vulnerability in X11 on AIX could allow a non-privileged local user to cause a buffer overflow that could result in a denial of service or arbitrary code execution (CVE-2022-47990). =============================================================================== VULNERABILITY DETAILS: CVEID: CVE-2022-47990 http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-47990 https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-47990 DESCRIPTION: IBM AIX could allow a non-privileged local user to exploit a vulnerability in X11 to cause a buffer overflow that could result in a denial of service or arbitrary code execution. CVSS Base Score: 6.2 CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/243556 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 7.1, 7.2, 7.3 VIOS 3.1 The following fileset levels are vulnerable: key_fileset = aix Fileset Lower Level Upper Level KEY --------------------------------------------------------- X11.base.lib 7.1.5.0 7.1.5.34 key_w_fs X11.base.lib 7.2.5.0 7.2.5.1 key_w_fs X11.base.lib 7.2.5.100 7.2.5.100 key_w_fs X11.base.lib 7.3.0.0 7.3.0.0 key_w_fs 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 X11.base.lib REMEDIATION: A. APARS IBM has assigned the following APARs to this problem: AIX Level APAR Availability SP KEY ----------------------------------------------------- 7.1.5 IJ43073 ** SP11 key_w_apar 7.2.5 IJ42677 ** SP05 key_w_apar 7.3.0 IJ42939 ** SP03 key_w_apar VIOS Level APAR Availability SP KEY ----------------------------------------------------- 3.1.2 IJ43599 ** 3.1.2.50 key_w_apar 3.1.3 IJ43218 ** 3.1.3.30 key_w_apar Subscribe to the APARs here: https://www.ibm.com/support/pages/apar/IJ42677 https://www.ibm.com/support/pages/apar/IJ42939 https://www.ibm.com/support/pages/apar/IJ43073 https://www.ibm.com/support/pages/apar/IJ43218 https://www.ibm.com/support/pages/apar/IJ43599 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 fixes can be downloaded via sftp or https from: https://aix.software.ibm.com/aix/efixes/security/x11_fix.tar The links above are 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 (*.Z) KEY ---------------------------------------------- 7.1.5.8 IJ43073sAa.221227.epkg.Z key_w_fix 7.1.5.9 IJ43073sAa.221227.epkg.Z key_w_fix 7.1.5.10 IJ43073sAa.221227.epkg.Z key_w_fix 7.2.5.3 IJ42677s4a.221227.epkg.Z key_w_fix 7.2.5.4 IJ42677s4a.221227.epkg.Z key_w_fix 7.3.0.1 IJ42939s2a.221227.epkg.Z key_w_fix 7.3.0.2 IJ42939s2a.221227.epkg.Z key_w_fix 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 (*.Z) KEY ----------------------------------------------- 3.1.2.21 IJ43599s2a.221227.epkg.Z key_w_fix 3.1.2.30 IJ43599s2a.221227.epkg.Z key_w_fix 3.1.2.40 IJ43599s2a.221227.epkg.Z key_w_fix 3.1.3.10 IJ43218s4a.221227.epkg.Z key_w_fix 3.1.3.14 IJ43218s4a.221227.epkg.Z key_w_fix 3.1.3.21 IJ43218s4a.221227.epkg.Z key_w_fix To extract the fixes from the tar file: tar xvf x11_fix.tar cd x11_fix Verify you have retrieved the fixes intact: The checksums below were generated using the "openssl dgst -sha256 [file]" command as the following: openssl dgst -sha256 filename KEY ----------------------------------------------------------------------------------------------------- 14cbb2b9dd2ef656fecad2435cbaa25e671f4af95687157976f98353e53188c4 IJ42677s4a.221227.epkg.Z key_w_csum 244a069d456404b1bccc17c200bbcc590b2de6b8b9fdfe9508f1ef719b28395a IJ42939s2a.221227.epkg.Z key_w_csum 4154bb1dcbcee62e94ffb5bb6ab797fed074c7c81f101bbbe93c59adadb073b3 IJ43073sAa.221227.epkg.Z key_w_csum 47b0da532dde030e744ec65d2fb816475de656e4b1494f36a575fb76311a08b2 IJ43218s4a.221227.epkg.Z key_w_csum a978251ccc42081acf62b9adf4619fcb07d75e83d215dd8a4e5e4a78fe2136fc IJ43599s2a.221227.epkg.Z key_w_csum 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 AIX Support at https://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: https://aix.software.ibm.com/aix/efixes/security/x11_advisory.asc.sig C. FIX AND INTERIM FIX INSTALLATION 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. =============================================================================== 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": https://www.ibm.com/support/mynotifications To view previously issued advisories, please visit: https://www14.software.ibm.com/webapp/set2/subscriptions/onvdq Contact IBM Support for questions related to this announcement: https://ibm.com/support/ 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 Please contact your local IBM AIX support center for any assistance. REFERENCES: Review this information as needed, no action required. 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 buffer overflow due to X11 (CVE-2022-47990) https://www.ibm.com/support/pages/node/6855827 ACKNOWLEDGEMENTS: None. CHANGE HISTORY: First Issued: Tue Jan 17 09:54:47 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.