IBM SECURITY ADVISORY First Issued: Thu Oct 18 09:50:27 CDT 2012 The most recent version of this document is available here: | Updated: Fri Feb 8 11:58:57 CDT 2013 | Update: Updated Sections I and V: Description and Workaround | Update: New ifixes for latest SP's | Updated: Thu Dec 12 12:55:11 CST 2013 | Update: 1. Added KEYs for parsing purposes | 2. Moved to OpenSSL signature http://aix.software.ibm.com/aix/efixes/security/ftp_advisory1.asc ftp://aix.software.ibm.com/aix/efixes/security/ftp_advisory1.asc =============================================================================== VULNERABILITY SUMMARY VULNERABILITY: AIX ftp vulnerability PLATFORMS: AIX 6.1 and 7.1 releases SOLUTION: Apply the fix as described below. THREAT: See below CVE Numbers: CVE-2012-4845 CVSS=6.8 Reboot required? YES Workarounds? YES Protected by FPM? NO Protected by SED? NO =============================================================================== DETAILED INFORMATION I. DESCRIPTION | The root owned files can be read by non-root users only when the directory | permissions are set allowed for non-root users. For example, a non-root user | won't be able to read anything under /etc/security, but can read files like | /etc/rc.wpars under ftp. (NOTE: See WORKAROUNDS (section V) below) II. CVSS CVSS Base Score: 6.8 CVSS Temporal Score: See http://xforce.iss.net/xforce/xfdb/79279 for the current score CVSS Environmental Score*: Undefined CVSS String: (AV:N/AC:L/Au:S/C:C/I:N/A:N) III. PLATFORM VULNERABILITY ASSESSMENT Note: To use the following commands on VIOS you must first execute: oem_setup_env To determine if your system is vulnerable, execute the following command: lslpp -L bos.mp64 bos.rte.tty The following fileset levels are vulnerable: AIX Fileset Lower Level Upper Level KEY ------------------------------------------------------------------ | bos.mp64 6.1.6.0 6.1.6.21 key_w_fs bos.rte.tty 6.1.6.0 6.1.6.19 key_w_fs | bos.mp64 6.1.7.0 6.1.7.17 key_w_fs bos.rte.tty 6.1.7.0 6.1.7.16 key_w_fs | bos.mp64 6.1.8.0 6.1.8.1 key_w_fs | bos.mp64 7.1.0.0 7.1.0.21 key_w_fs bos.rte.tty 7.1.0.0 7.1.0.18 key_w_fs | bos.mp64 7.1.1.0 7.1.1.17 key_w_fs bos.rte.tty 7.1.1.0 7.1.1.16 key_w_fs | bos.mp64 7.1.2.0 7.1.2.1 key_w_fs IV. SOLUTIONS A. APARS IBM has assigned the following APARs to this problem: AIX Level APAR Availability SP KEY --------------------------------------------------- | 6.1.6 IV28715 03/29/13 sp11 key_w_apar | 6.1.7 IV23331 03/29/13 sp7 key_w_apar | 6.1.8 IV28651 03/08/13 sp2 key_w_apar | 7.1.0 IV28785 05/02/13 sp9 key_w_apar | 7.1.1 IV28787 05/02/13 sp7 key_w_apar | 7.1.2 IV30669 03/08/13 sp2 key_w_apar Subscribe to the APARs here: http://www.ibm.com/support/docview.wss?uid=isg1IV28715 http://www.ibm.com/support/docview.wss?uid=isg1IV23331 | http://www.ibm.com/support/docview.wss?uid=isg1IV28651 http://www.ibm.com/support/docview.wss?uid=isg1IV28785 http://www.ibm.com/support/docview.wss?uid=isg1IV28787 | http://www.ibm.com/support/docview.wss?uid=isg1IV30669 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 Fixes are available. The fixes can be downloaded via ftp from: ftp://aix.software.ibm.com/aix/efixes/security/ftp_fix1.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 (*.Z) KEY ------------------------------------------------------------------- 6.1.6.9 IV28715m09.121012.epkg.Z key_w_fix (bos.mp64 only) | 6.1.6.10 IV28715sAa.130206.epkg.Z key_w_fix 6.1.7.5 IV23331m05.121003.epkg.Z key_w_fix (bos.mp64 only) | 6.1.7.6 IV23331s6a.121226.epkg.Z key_w_fix (bos.mp64 only) | 6.1.8.1 IV28651s1a.121204.epkg.Z key_w_fix 7.1.0.7 IV28785m07.121002.epkg.Z key_w_fix (bos.mp64 only) | 7.1.0.8 IV28785s8a.130206.epkg.Z key_w_fix 7.1.1.5 IV28787m05.121002.epkg.Z key_w_fix (bos.mp64 only) | 7.1.1.6 IV28787s6a.130121.epkg.Z key_w_fix (bos.mp64 only) | 7.1.2.1 IV30669s1a.130114.epkg.Z key_w_fix VIOS Level Interim Fix (*.Z) ------------------------------------------------------------------- VIOS 2.2.1.4-FP-25 SP-02 IV23331m04.121003.epkg.Z To extract the fixes from the tar file: tar xvf ftp_fix1.tar cd ftp_fix1 Verify you have retrieved the fixes intact: The checksums below were generated using the "csum -h SHA1" (sha1sum) command is the followng: csum -h SHA1 (sha1sum) filename ------------------------------------------------------------------ 4ba2810c2f7b909d9c9d6aa9aa2c8598ae5cd3c9 IV28715m09.121012.epkg.Z | a35fc018a472ab8b9081904af3179287067f4b1b IV28715sAa.130206.epkg.Z 6a5378ebfd9fc9172705798c6763b73b86385188 IV23331m05.121003.epkg.Z | da0232eb934334ad29207b40f9592723ef5f73cd IV23331s6a.121226.epkg.Z | 7ed082bf24b1608b5f16fe46f9f5251804a51619 IV28651s1a.121204.epkg.Z e8ef9337f5460b7b2b2c6334727721a07d0400e1 IV28785m07.121002.epkg.Z | 5e4912c6528cfba7dfc2a15f1857abdcf1731ccc IV28785s8a.130206.epkg.Z 4296229d6731a9f1862502aa6a5a86f785bebcf0 IV28787m05.121002.epkg.Z | 2a70ef9589b50bbc26d82ef0c265758d71ebc4fe IV28787s6a.130121.epkg.Z | 6a71f6b5d8c3c62b838354a85a99e570b9454d61 IV30669s1a.130114.epkg.Z bcf1d9b2a661255b90bbe8aa85e7ddf56a6ce5ca IV23331m04.121003.epkg.Z To verify the sum, use the text of this advisory as input to sha1sum. For example: csum -h SHA1 -i Advisory.asc sha1sum -c Advisory.asc 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 Security at security-alert@austin.ibm.com and describe the discrepancy. openssl dgst -sha1 -verify AIX_PSIRT_pub.asc -signature file.asc.sig file.asc C. FIX AND INTERIM FIX INSTALLATION 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 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. V. WORKAROUNDS | The following command specifies to remove the innate privilege, PV_DAC_R, | from the security attributes of the ftp command: | # setsecattr -c innateprivs=-PV_DAC_R /usr/bin/ftp | And then resets the entry in the kernel security table (KST) | # setkst | This workaround is sufficient to remove the ftp vulnerability. VI. CONTACT INFORMATION If you would like to receive AIX Security Advisories via email, please visit: http://www.ibm.com/systems/support and click on the "My notifications" link. To view previously issued advisories, please visit: | http://www14.software.ibm.com/webapp/set2/subscriptions/onvdq Comments regarding the content of this announcement can be directed to: security-alert@austin.ibm.com To obtain the OpenSSL public key that can be used to verify the signed advisories and ifixes: Download the key from our web page: http://www.ibm.com/systems/resources/systems_p_os_aix_security_pubkey.txt To obtain the PGP public key that can be used to communicate securely with the AIX Security Team you can either: A. Send an email with "get key" in the subject line to: security-alert@austin.ibm.com B. Download the key from a PGP Public Key Server. The key ID is: 0x28BFAA12 Please contact your local IBM AIX support center for any assistance. eServer is a trademark of International Business Machines Corporation. IBM, AIX and pSeries are registered trademarks of International Business Machines Corporation. All other trademarks are property of their respective holders. VII. ACKNOWLEDGMENTS IBM discovered and fixed this vulnerability as part of its commitment to secure the AIX operating system. VIII. REFERENCES: Note: Keywords labeled as KEY in this document are used for parsing purposes. Complete CVSS Guide: http://www.first.org/cvss/cvss-guide.html On-line Calculator V2: http://nvd.nist.gov/cvss.cfm?calculator&adv&version=2 X-Force Vulnerability Database: http://xforce.iss.net/xforce/xfdb/79279 CVE-2012-4845: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-4845 *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 Flash. Note: 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.