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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2006.0692 -- [AIX] Vulnerabilities in utape may allow for arbitrary command execution and arbitrary file overwrite 26 September 2006 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: utape Publisher: IBM Operating System: AIX 5.3 and 5.2 Impact: Root Compromise Denial of Service 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: Arbitrary file overwrite and incomplete path vulnerabilities in utape command. PLATFORMS: AIX 5.2 and 5.3. SOLUTION: Apply the APAR, interim fix or workaround as described below. THREAT: A local user may cause a denial of service or execute arbitrary commands with root privileges. CERT VU Number: n/a CVE Number: n/a ========================================================================== DETAILED INFORMATION I. Description =============== Two vulnerabilities exist in the utape command. These vulnerabilities can only be exploited by a user if that user is both in the system group and has the "Diagnostics" role. First, a vulnerability exists that will allow a local user to execute arbitrary commands with root privileges. Second, a vulnerability exists that will allow a local user to overwrite an arbitrary system file resulting in a denial of service. utape ships as part of the devices.scsi.tape.diag fileset. To determine if this fileset is installed, execute the following command: # lslpp -L devices.scsi.tape.diag 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 devices.scsi.tape.diag: AIX Release Lower Upper Level Level =========================================== AIX 5.2 5.2.0.0 5.2.0.75 AIX 5.3 5.3.0.0 5.3.0.30 II. Impact ========== A local user may execute arbitrary commands or overwrite an arbitrary file resulting in a denial of service. III. Solutions =============== A. APARs IBM provides the following fixes: APAR number for AIX 5.2.0: IY88641 (available approx. 10/18/06) APAR number for AIX 5.3.0: IY88642 (available approx. 11/01/06) NOTE: Affected customers are urged to upgrade to the latest applicable Technology Level. B. Interim Fix Interim fixes are available. The interim fixes can be downloaded via ftp from: ftp://aix.software.ibm.com/aix/efixes/security/utape_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. The checksums below were generated using the "sum" and "md5sum" commands and are as follows: Filename sum md5 ========================================================================= IY88641_07.060824.epkg.Z 49985 25 3109a163f3b09041b431866988c3f332 IY88641_08.060824.epkg.Z 47659 25 4b077a04542e9e77c6f5424f098e52e0 IY88641_09.060824.epkg.Z 44860 25 ced7d54998885cbd225289d0e07b4683 IY88642_03.060824.epkg.Z 48193 25 eeafca7b458be572f271e2d9ca43cb3a IY88642_04.060824.epkg.Z 21572 25 ae72e10aacbd0263e4ebf3d4e063ae79 IY88642_05.060824.epkg.Z 27641 25 68d846f354bce4ba704954f7e54cd1a8 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 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 devices.scsi.tape.diag. Interim Fileset Level Fileset Level Fix (lower limit) (upper limit) =================================================================== IY88641_07.060824.epkg.Z 5.2.0.75 5.2.0.75 IY88641_08.060824.epkg.Z 5.2.0.75 5.2.0.75 IY88641_09.060824.epkg.Z 5.2.0.75 5.2.0.75 IY88642_03.060824.epkg.Z 5.3.0.30 5.3.0.30 IY88642_04.060824.epkg.Z 5.3.0.30 5.3.0.30 IY88642_05.060824.epkg.Z 5.3.0.30 5.3.0.30 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 root bit. Note that this will prevent utape from functioning normally for non-root users. This can be done by executing the following command: # chmod 550 /usr/lpp/diagnostics/bin/utape Verify the changes: # ls -la /usr/lpp/diagnostics/bin/utape - - -r-xr-x--- 1 root system 36580 Oct 1 2004 /usr/lpp/diagnostics/bin/utape 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 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) iD8DBQFFF/4CofN/JhsU8pkRAm1UAJ9BfM30sfEZ1770Ae/gdvYO2apd5ACeIsSQ 1qxopWZNSdUbJmsEs2DmasE= =CzBe - -----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 auscert@auscert.org.au 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. As AusCERT did not write the document quoted above, AusCERT has had no control over its content. The decision to follow or act on information or advice contained in this security bulletin is the responsibility of each user or organisation, and should be considered in accordance with your organisation's site policies and procedures. AusCERT takes no responsibility for consequences which may arise from following or acting on information or advice contained in this security bulletin. NOTE: This is only the original release of the security bulletin. It may not be updated when updates to the original are made. 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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: auscert@auscert.org.au 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 iQCVAwUBRRiRuCh9+71yA2DNAQJw3AP/Y+PbT6dW0GsVmVXcnk8nQooV2LNNZOqc oCubXVQgm9BEBIhwllnvSvDqBGOXXp+op8/xaaiW57vt18Pt9uxNF8iW3gJt0q1+ wsYMImuapHmJYwmsxoj4+3A8QibAkiccrYf0UzZ5dIJ8PrZhbsmG2W9Xoyb0Ax4x gDNgyB3ZzXY= =FJta -----END PGP SIGNATURE-----