===================================================================== CERT-Renater Note d'Information No. 2006/VULN175 _____________________________________________________________________ DATE : 19/04/2006 HARDWARE PLATFORM(S) : / OPERATING SYSTEM(S) : AIX 5.1, 5.2 and 5.3 ====================================================================== - -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 IBM SECURITY ADVISORY First Issued: Mon Apr 17 10:20:50 CDT 2006 ========================================================================== VULNERABILITY SUMMARY VULNERABILITY: A user in the system group may execute arbitrary code with root privileges. PLATFORMS: AIX 5.3. SOLUTION: Apply the APAR, interim fix or workaround as described below. THREAT: A user in the system group may execute arbitrary code with root privileges. CERT VU Number: n/a CVE Number: CVE-2006-1246 ========================================================================= DETAILED INFORMATION I. Description =============== A vulnerability was discovered in the mklvcopy command that allows a local user in the system group to execute arbitrary code. The mklvcopy command is used to increase the number of copies in each logical partition of a logical volume. mklvcopy ships as part of the bos.rte.lvm fileset. II. Impact ========== A local user in the system group may execute arbitrary code with root privileges. III. Solutions =============== A. Official Fix IBM provides the following fixes: APAR number for AIX 5.3.0: IY82739 (available) NOTE: Affected customers are urged to upgrade to the latest applicable Technology Level. B. Interim Fix Interim fixes are available. The ifixes can be downloaded via ftp from: ftp://aix.software.ibm.com/aix/efixes/security/mklvcopy_ifix.tar.Z mklvcopy_ifix.tar.Z is a compressed tarball containing this advisory, ifix packages and cleartext PGP signatures for each ifix 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. The checksums below were generated using the "sum" and "md5sum" commands and are as follows: Filename sum md5 ======================================================================== IY82739_02.060313.epkg.Z 59853 14 7b9c54e62d34b80edd03caeb81378b11 IY82739_03.060313.epkg.Z 00809 14 1a43e0029c87bf2dbbdf3762c693d434 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 security-alert@austin.ibm.com and describe the discrepancy. The following table shows the prerequisite lower and upper fileset levels for the fixes above. These levels are inclusive and apply to bos.rte.lvm. Technology Filename Lower Level Upper Level Level =================================================================== 5300-02 IY82739_02.060313.epkg.Z 5.3.0.10 5.3.0.29 5300-03 IY82739_03.060313.epkg.Z 5.3.0.30 5.3.0.39 IMPORTANT: If possible, it is recommended that a mksysb backup of the system is created. Verify it is both bootable, and readable before proceeding. These ifixes have not been fully regression tested; thus, IBM does not warrant the fully correct functioning of the ifix. Customers install the ifix and operate the modified version of AIX at their own risk. Interim Installation Instructions: +--------------------------------- These packages use the new Interim Fix Management Solution to install and manage ifixes. More information can be found at: http://www14.software.ibm.com/webapp/set2/sas/f/aix.efixmgmt/home.html To preview an epkg ifix installation execute the following command: # emgr -e ipkg_name -p # where ipkg_name is the name of the # ifix package being previewed. To install an epkg ifix package, execute the following command: # emgr -e ipkg_name -X # where ipkg_name is the name of the # ifix package being installed. The "X" flag will expand any filesystems if required. C. Workaround Make mklvcopy executable only by the root user +--------------------------------------------- To make mklvcopy executable only by root, run the following commands: # chmod 500 /usr/sbin/mklvcopy Verify the that the file mode bits have been updated: # ls -la /usr/sbin/mklvcopy - - -r-x------ 1 root system 19354 Feb 15 10:25 /usr/sbin/mklvcopy Note that users in the system group will not be able to use the mklvcopy command. 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: security-alert@austin.ibm.com To request the PGP public key that can be used to communicate securely with the AIX Security Team send email to security-alert@austin.ibm.com with a subject of "get key". The key can also be downloaded from a PGP Public Key Server. The key id is 0x9391C1F2. 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 v1.4.1 (GNU/Linux) iD8DBQFEQ7SaxwSSvpORwfIRApaDAJoDQqz/Zv/qobOClKXmF1c53WQyrgCcCS7H hYBIrX8wzGRtYDP9XClGMbM= =ozOM - -----END PGP SIGNATURE----- ====================================================================== ========================================================= Les serveurs de référence du CERT-Renater http://www.urec.fr/securite http://www.cru.fr/securite http://www.renater.fr ========================================================= + CERT-RENATER | tel : 01-53-94-20-44 + + 151 bd de l'Hopital | fax : 01-53-94-20-41 + + 75013 Paris | email: certsvp@renater.fr + =========================================================