-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 IBM SECURITY ADVISORY First Issued: Mon Mar 29 15:54:57 CDT 2010 The most recent version of this document is available here: http://aix.software.ibm.com/aix/efixes/security/sendmail_advisory.asc VULNERABILITY SUMMARY VULNERABILITY: AIX sendmail SSL certificate vulnerability PLATFORMS: AIX 5.3, 6.1 VIOS 1.5, 2.1 SOLUTION: Apply the fix or workaround as described below. THREAT: A man-in-the-middle attacker may be able to spoof arbitrary SSL SMTP servers CERT VU Number: n/a CVE Number: CVE-2009-4565 Reboot required? NO Workarounds? NO Protected by FPM? NO Protected by SED? NO DETAILED INFORMATION I. DESCRIPTION (from CVE) "sendmail before 8.14.4 does not properly handle a '\0' character in a Common Name (CN) field of an X.509 certificate, which (1) allows man-in-the-middle attackers to spoof arbitrary SSL-based SMTP servers via a crafted server certificate issued by a legitimate Certification Authority, and (2) allows remote attackers to bypass intended access restrictions via a crafted client certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408." II. 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.net.tcp.client The following fileset levels are vulnerable: AIX Fileset Lower Level Upper Level ------------------------------------------------ bos.net.tcp.client 5.3.8.0 5.3.8.11 bos.net.tcp.client 5.3.9.0 5.3.9.7 bos.net.tcp.client 5.3.10.0 5.3.10.2 bos.net.tcp.client 5.3.11.0 5.3.11.2 bos.net.tcp.client 6.1.1.0 6.1.1.7 bos.net.tcp.client 6.1.2.0 6.1.2.6 bos.net.tcp.client 6.1.3.0 6.1.3.3 bos.net.tcp.client 6.1.4.0 6.1.4.3 III. SOLUTION A. FIXES Fixes are now available. The fixes are interim fixes. The fixes can be downloaded from: http://aix.software.ibm.com/aix/efixes/security/sendmail_fix.tar The links above are to a tar file containing this signed advisory, fix packages, and PGP signatures for each package. AIX Level VIOS Level Fix ------------------------------------------------------ 5.3.8 1.5.2 IZ72834_08.100329.epkg.Z 5.3.9 IZ72835_09.100329.epkg.Z 5.3.10 IZ72836_10.100329.epkg.Z 5.3.11 IZ72837_11.100329.epkg.Z 6.1.1 IZ72528_01.100329.epkg.Z 6.1.2 2.1.0 IZ72515_02.100329.epkg.Z 6.1.3 2.1.1 IZ72510_03.100329.epkg.Z 6.1.4 2.1.2 IZ70637_04.100329.epkg.Z To extract the fixes from the tar file: tar xvf sendmail_fix.tar cd sendmail_fix Verify you have retrieved the fixes intact: The checksums below were generated using the "csum -h SHA1" (sha1sum) commands and are as follows: csum -h SHA1 (sha1sum) filename ------------------------------------------------------------------ 5643989ef10e97eba58fb49c1399dc35fd4efe59 IZ70637_04.100329.epkg.Z 9c3341316809bb06962840aa0f18157878784ec7 IZ72510_03.100329.epkg.Z 261613c73338faeaffc69b5c6314b737ac6c52a1 IZ72515_02.100329.epkg.Z 8b529961f722c4df077ba00a50d8daf293d64d71 IZ72528_01.100329.epkg.Z 4a21abf1366ed3d0052c0fcf064ff01be546447a IZ72834_08.100329.epkg.Z b30e05ec7a60e89ccbca0bad0b9092f38795ec98 IZ72835_09.100329.epkg.Z 7821837e1954ebac5d83485348984033c93c8667 IZ72836_10.100329.epkg.Z 3bfabc5510c3d55b9c599d8bae17b11e4967bf64 IZ72837_11.100329.epkg.Z To verify the sums, use the text of this advisory as input to csum or sha1sum. For example: csum -h SHA1 -i sendmail_advisory.asc sha1sum -c sendmail_advisory.asc These sums should match exactly. The PGP 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 and describe the discrepancy at the following addresses: security-alert@austin.ibm.com ahazlewo@us.ibm.com (Andy Hazlewood) B. 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. Fix management documentation can be found at: http://www14.software.ibm.com/webapp/set2/sas/f/aix.efixmgmt/home.html To preview fix installation: emgr -e fix_name -p # where fix_name is the name of the # fix being previewed. To install fix package: emgr -e fix_name -X # where fix_name is the name of the # fix being installed. IMPORTANT: The fix will not take affect until any running sendmail servers have been stopped and restarted with the following commands: stopsrc -s sendmail startsrc -s'sendmail' -a'-bd -q30m' C. APARS IBM has assigned the following APARs to this problem: AIX Level APAR number Service pack date -------------------------------------------------------- 5.3.8 IZ72834 5/19/10 sp10 5.3.9 IZ72835 5/19/10 sp7 5.3.10 IZ72836 5/19/10 sp4 5.3.11 IZ72837 5/19/10 sp4 6.1.1 IZ72528 4/21/10 sp8 6.1.2 IZ72515 4/21/10 sp7 6.1.3 IZ72510 4/21/10 sp4 6.1.4 IZ70637 4/21/10 sp4 Subscribe to the APARs here: http://www.ibm.com/support/docview.wss?uid=isg1IZ72834 http://www.ibm.com/support/docview.wss?uid=isg1IZ72835 http://www.ibm.com/support/docview.wss?uid=isg1IZ72836 http://www.ibm.com/support/docview.wss?uid=isg1IZ72837 http://www.ibm.com/support/docview.wss?uid=isg1IZ72528 http://www.ibm.com/support/docview.wss?uid=isg1IZ72515 http://www.ibm.com/support/docview.wss?uid=isg1IZ72510 http://www.ibm.com/support/docview.wss?uid=isg1IZ70637 By subscribing, you will receive periodic email alerting you to the status of the APAR, and a link to download the service pack when it becomes available. IV. WORKAROUND None. 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/pqvcmjd Comments regarding the content of this announcement can be directed to: security-alert@austin.ibm.com ahazlewo@us.ibm.com (Andy Hazlewood) 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 our web page: http://www.ibm.com/systems/resources/systems_p_os_aix_security_pgpkey.txt C. Download the key from a PGP Public Key Server. The key ID is: 0xF3807ECD 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 This vulnerability was reported by sendmail.org for an issue found by Moxie Marlinspike. This advisory was written by Andy Hazlewood (ahazlewo@us.ibm.com). -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (AIX) iD8DBQFLshIJxvGNyvOAfs0RAqrCAKCE8qpzbW+cZ87GgA6pMm8QCTY7XwCfbg8N mBR8IALfZXJqaL2QTNm741c= =XgvM -----END PGP SIGNATURE-----