===================================================================== CERT-Renater Note d'Information No. 2005/VULN126 _____________________________________________________________________ DATE : 25/02/2005 HARDWARE PLATFORM(S) : / OPERATING SYSTEM(S) : Systems running cyrus-imapd. ====================================================================== ______________________________________________________________________________ SUSE Security Announcement Package: cyrus-imapd Announcement-ID: SUSE-SA:2005:009 Date: Thu, 24 Feb 2005 14:00:00 +0000 Affected products: 8.2, 9.0, 9.1, 9.2 SUSE Linux Enterprise Server 8, 9 Vulnerability Type: remote code execution Severity (1-10): 7 SUSE default package: yes Cross References: None. Content of this advisory: 1) security vulnerability resolved: several 1 byte buffer overflows fixed 2) solution/workaround 3) special instructions and notes 4) package location and checksums 5) pending vulnerabilities, solutions, workarounds: See SUSE Security Summary Report. 6) standard appendix (further information) ______________________________________________________________________________ 1) problem description, brief discussion This update fixes one-byte buffer overruns in the cyrus-imapd IMAP server package. Several overruns were fixed in the IMAP annote extension as well as in cached header handling which can be run by an authenticated user. Additionally bounds checking in fetchnews was improved to avoid exploitation by a peer news admin. Please note that one-byte buffer overflows can not be exploited to execute arbitrary commands by manipulating the saved registers on the stack if the compiler used (gcc >= 3) aligns the stack space. Nevertheless the code behavior may be manipulated by overwriting local variables. The result is not known but ranges between a denial-of-service condition and privilege escalation. This update backports bugfixes from the upstream release of cyrus-imapd 2.2.11 announced on: http://asg.web.cmu.edu/archive/message.php?mailbox=archive.info-cyrus&msg=33723 2) solution/workaround Install the updated packages. Make sure you restart cyrus-imapd by running /sbin/rccyrus try-restart 3) special instructions and notes None. 4) package location and checksums Please download the update package for your distribution and verify its integrity by the methods listed in section 3) of this announcement. Then, install the package using the command "rpm -Fhv file.rpm" to apply the update. Our maintenance customers are being notified individually. The packages are being offered to install from the maintenance web. x86 Platform: SUSE Linux 9.2: ftp://ftp.suse.com/pub/suse/i386/update/9.2/rpm/i586/cyrus-imapd-2.2.8-6.5.i586.rpm 3bfbec25eb82d07a8195fb621876cf4b SUSE Linux 9.1: ftp://ftp.suse.com/pub/suse/i386/update/9.1/rpm/i586/cyrus-imapd-2.2.3-83.22.i586.rpm e90855625f9d66bed10f0d601517ca7f SUSE Linux 9.0: ftp://ftp.suse.com/pub/suse/i386/update/9.0/rpm/i586/cyrus-imapd-2.1.15-91.i586.rpm b3f0a8e7ab5780b2544a2c5ce9671b18 SUSE Linux 8.2: ftp://ftp.suse.com/pub/suse/i386/update/8.2/rpm/i586/cyrus-imapd-2.1.12-77.i586.rpm 989a125263e4388b2e3825262e495923 x86-64 Platform: SUSE Linux 9.2: ftp://ftp.suse.com/pub/suse/i386/update/9.2/rpm/x86_64/cyrus-imapd-2.2.8-6.5.x86_64.rpm 267540ff1676d534dc0bab3b075a0b32 source rpm(s): ftp://ftp.suse.com/pub/suse/i386/update/9.2/rpm/src/cyrus-imapd-2.2.8-6.5.src.rpm 8f78ab5817abd9a354473a6f10f6c5d5 SUSE Linux 9.1: ftp://ftp.suse.com/pub/suse/x86_64/update/9.1/rpm/x86_64/cyrus-imapd-2.2.3-83.22.x86_64.rpm 0b51738a00dbb8cc71d1277d1b370576 source rpm(s): ftp://ftp.suse.com/pub/suse/x86_64/update/9.1/rpm/src/cyrus-imapd-2.2.3-83.22.src.rpm b1316bfae2476c5e880e581893cad224 SUSE Linux 9.0: ftp://ftp.suse.com/pub/suse/x86_64/update/9.0/rpm/x86_64/cyrus-imapd-2.1.15-91.x86_64.rpm 4c5bc7aa5de6ca5a9ef2758b17b20ba3 source rpm(s): ftp://ftp.suse.com/pub/suse/x86_64/update/9.0/rpm/src/cyrus-imapd-2.1.15-91.src.rpm c6ce2fd455ddc73b00e4092b5332335f ______________________________________________________________________________ 5) Pending vulnerabilities in SUSE Distributions and Workarounds: See SUSE Security Summary Report. ______________________________________________________________________________ 6) standard appendix: authenticity verification, additional information - Package authenticity verification: SUSE update packages are available on many mirror ftp servers all over the world. While this service is being considered valuable and important to the free and open source software community, many users wish to be sure about the origin of the package and its content before installing the package. There are two verification methods that can be used independently from each other to prove the authenticity of a downloaded file or rpm package: 1) md5sums as provided in the (cryptographically signed) announcement. 2) using the internal gpg signatures of the rpm package. 1) execute the command md5sum after you downloaded the file from a SUSE ftp server or its mirrors. Then, compare the resulting md5sum with the one that is listed in the announcement. Since the announcement containing the checksums is cryptographically signed (usually using the key security@suse.de), the checksums show proof of the authenticity of the package. We disrecommend to subscribe to security lists which cause the email message containing the announcement to be modified so that the signature does not match after transport through the mailing list software. Downsides: You must be able to verify the authenticity of the announcement in the first place. If RPM packages are being rebuilt and a new version of a package is published on the ftp server, all md5 sums for the files are useless. 2) rpm package signatures provide an easy way to verify the authenticity of an rpm package. Use the command rpm -v --checksig to verify the signature of the package, where is the filename of the rpm package that you have downloaded. Of course, package authenticity verification can only target an un-installed rpm package file. Prerequisites: a) gpg is installed b) The package is signed using a certain key. The public part of this key must be installed by the gpg program in the directory ~/.gnupg/ under the user's home directory who performs the signature verification (usually root). You can import the key that is used by SUSE in rpm packages for SUSE Linux by saving this announcement to a file ("announcement.txt") and running the command (do "su -" to be root): gpg --batch; gpg < announcement.txt | gpg --import SUSE Linux distributions version 7.1 and thereafter install the key "build@suse.de" upon installation or upgrade, provided that the package gpg is installed. The file containing the public key is placed at the top-level directory of the first CD (pubring.gpg) and at ftp://ftp.suse.com/pub/suse/pubring.gpg-build.suse.de . - SUSE runs two security mailing lists to which any interested party may subscribe: suse-security@suse.com - general/linux/SUSE security discussion. All SUSE security announcements are sent to this list. To subscribe, send an email to . suse-security-announce@suse.com - SUSE's announce-only mailing list. Only SUSE's security announcements are sent to this list. To subscribe, send an email to . For general information or the frequently asked questions (faq) send mail to: or respectively. ===================================================================== SUSE's security contact is or . @suse.de>. The public key is listed below. ===================================================================== ______________________________________________________________________________ The information in this advisory may be distributed or reproduced, provided that the advisory is not modified in any way. In particular, it is desired that the clear-text signature shows proof of the authenticity of the text. SUSE Linux AG makes no warranties of any kind whatsoever with respect to the information contained in this security advisory. Type Bits/KeyID Date User ID pub 2048R/3D25D3D9 1999-03-06 SuSE Security Team pub 1024D/9C800ACA 2000-10-19 SuSE Package Signing Key ====================================================================== ========================================================= 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 + =========================================================