26 September 2006
Protect yourself against future threats.
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2006.0696 -- [AIX] Vulnerability in mkvg may allow for arbitrary command execution 26 September 2006 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: mkvg Publisher: IBM Operating System: AIX 5.3 AIX 5.2 Impact: Root Compromise Access: Existing Account - --------------------------BEGIN INCLUDED TEXT-------------------- - -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 IBM SECURITY ADVISORY First Issued: Mon Sep 25 10:00 CDT 2006 ========================================================================== VULNERABILITY SUMMARY VULNERABILITY: An incomplete path vulnerability in the mkvg command may allow a local user in the system group to execute arbitrary commands with root privileges. PLATFORMS: AIX 5.2 and 5.3. SOLUTION: Apply the APAR, interim fix or workaround as described below. THREAT: A local user may execute arbitrary code. CERT VU Number: n/a CVE Number: n/a ========================================================================== DETAILED INFORMATION I. Description =============== A vulnerability was discovered in the mkvg command which may allow a local user in the system group to execute arbitrary code with root privileges. extendvg and mkvg are hardlinks to the same executable. These commands are used to manage volume groups. The mkvg command ships as part of the bos.rte.lvm fileset. To determine if a fileset is installed, execute the following command: # lslpp -L bos.rte.lvm If the fileset is installed, it will be listed along with its version information, state, type and a description. The following table shows the vulnerable versions of bos.rte.lvm. AIX Release Lower Upper Level Level =========================================== AIX 5.2 22.214.171.124 126.96.36.199 AIX 5.3 188.8.131.52 184.108.40.206 II. Impact ========== A local user in the system group may execute arbitrary code with root privileges. III. Solutions =============== A. APARs IBM provides the following fixes: APAR number for AIX 5.2.0: IY88722 (available) APAR number for AIX 5.3.0: IY88699 (available approx. 10/04/06) NOTE: Affected customers are urged to upgrade to the latest applicable Technology Level. B. Interim Fix Interim fixes are currently available. The interim fixes can be downloaded via ftp from: ftp://aix.software.ibm.com/aix/efixes/security/mkvg_ifix.tar.Z This is a compressed tarball containing this advisory, interim fix packages and cleartext PGP signatures for each package. Verify you have retrieved the fixes intact: +------------------------------------------ The interim fixes below are named by using the APAR corresponding to the release that the fix applies to. The APAR is followed by an underscore and the Technology Level for the particular AIX release that a fix applies to. Filename sum md5 ========================================================================= IY88722_07.060908.epkg.Z 05480 19 2ad7419e7f75430396122a01e26efdf5 IY88722_08.060908.epkg.Z 02692 19 e123b6aa85fc172ed34f5772b002317d IY88722_09.060908.epkg.Z 07748 19 a240624a427b0a81ff1e5855e23c1837 IY88699_03.060824.epkg.Z 50074 22 41b76112f55deeba34a4a8a63c9fc3fb IY88699_04.060824.epkg.Z 23149 22 65dd39ec02ddc8c9732cfd31a2e4e79e IY88699_05.060829.epkg.Z 55859 22 07654d6d53bb9801d36c2757ebd6be32 These sums should match exactly. The PGP signatures in the compressed tarball and on this advisory can also be used to verify the integrity of the various files they correspond to. If the sums or signatures cannot be confirmed, double check the command results and the download site address. If those are OK, contact IBM AIX Security at firstname.lastname@example.org and describe the discrepancy. The interim fixes include prerequisite checking. This will ensure the correct mapping between the interim fixes and AIX Technology Levels. The following table shows the prerequisite fileset levels required for the fixes above. The fileset levels listed are for bos.rte.lvm. Interim Fileset Level Fileset Level Fix (lower limit) (upper limit) =================================================================== IY88722_07.060908.epkg.Z 220.127.116.11 18.104.22.168 IY88722_08.060908.epkg.Z 22.214.171.124 126.96.36.199 IY88722_09.060908.epkg.Z 188.8.131.52 184.108.40.206 IY88699_03.060824.epkg.Z 220.127.116.11 18.104.22.168 IY88699_04.060824.epkg.Z 22.214.171.124 126.96.36.199 IY88699_05.060829.epkg.Z 188.8.131.52 184.108.40.206 IMPORTANT: If possible, it is recommended that a mksysb backup of the system is created. Verify it is both bootable, and readable before proceeding. Customers may contact IBM support if any issues arise with these interim fixes. Interim Installation Instructions: +--------------------------------- These packages use the new Interim Fix Management Solution to install and manage interim fixes. More information can be found at: http://www14.software.ibm.com/webapp/set2/sas/f/aix.efixmgmt/home.html To preview an epkg interim fix installation execute the following command: # emgr -e ipkg_name -p # where ipkg_name is the name of the # interim fix package being previewed. To install an epkg interim fix package, execute the following command: # emgr -e ipkg_name -X # where ipkg_name is the name of the # interim fix package being installed. The "X" flag will expand any filesystems if required. C. Workaround Remove the setuid bit. Note that this may prevent the mkvg and extendvg commands for functioning normally for non-root users. This can be done by executing the following command: # chmod 550 /usr/sbin/mkvg Verify the changes: # ls -la /usr/sbin/mkvg - - -r-xr-x--- 2 root system 26314 Mar 5 2005 /usr/sbin/mkvg IV. Obtaining Fixes =================== AIX Version 5 APARs can be downloaded from: http://www.ibm.com/servers/eserver/support/unixservers/aixfixes.html Security related Interim Fixes can be downloaded from: ftp://aix.software.ibm.com/aix/efixes/security V. Contact Information ======================= If you would like to receive AIX Security Advisories via email, please visit: http://www14.software.ibm.com/webapp/set2/subscriptions/pqvcmjd Comments regarding the content of this announcement can be directed to: email@example.com To request the PGP public key that can be used to communicate securely with the AIX Security Team send email to firstname.lastname@example.org with a subject of "get key". The key can also be downloaded from a PGP Public Key Server. The key id is 0x1B14F299. 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. - -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.3 (GNU/Linux) iD8DBQFFEsElofN/JhsU8pkRAi/CAJ9Yb6e0ucwxOCn/AIVQb/52rODriACdF1Jk 8vg3MVM3k8BNfEEg92KTnh4= =jiua - -----END PGP SIGNATURE----- - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. The mailing list you are subscribed to is maintained within your organisation, so if you do not wish to continue receiving these bulletins you should contact your local IT manager. If you do not know who that is, please send an email to email@example.com and we will forward your request to the appropriate person. NOTE: Third Party Rights This security bulletin is provided as a service to AusCERT's members. 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Previous advisories and external security bulletins can be retrieved from: http://www.auscert.org.au/render.html?cid=1980 If you believe that your computer system has been compromised or attacked in any way, we encourage you to let us know by completing the secure National IT Incident Reporting Form at: http://www.auscert.org.au/render.html?it=3192 =========================================================================== Australian Computer Emergency Response Team The University of Queensland Brisbane Qld 4072 Internet Email: firstname.lastname@example.org Facsimile: (07) 3365 7031 Telephone: (07) 3365 4417 (International: +61 7 3365 4417) AusCERT personnel answer during Queensland business hours which are GMT+10:00 (AEST). On call after hours for member emergencies only. =========================================================================== -----BEGIN PGP SIGNATURE----- Comment: http://www.auscert.org.au/render.html?it=1967 iQCVAwUBRRiv7Sh9+71yA2DNAQIxBAP/YNoZDBkJfNIcAuNE4EYYM7boVWfRlSJW Z+UZ6DHzP3RTcvfmkUiNHoytEjWwPwWtCUH1TBDZwU934DQMbaZuUe8WL5H6ZtYv cnUhvfwwcHxrv7YZmbjMfDMIeKBC44wo0OAU9wul8TSLLfMKmKW9xVg3PO+yzd3+ u9MkTUomxKQ= =V8fm -----END PGP SIGNATURE-----