______________________________________________________________________________ SuSE Security Announcement Package: hypermail Announcement-ID: SuSE-SA:2003:0012 Date: Thursday, Feb 27th 2003 18:30 MET Affected products: 7.1, 7.2, 7.3, 8.0, 8.1 Vulnerability Type: remote system compromise Severity (1-10): 4 SuSE default package: no Cross References: CAN-2003-0025 Content of this advisory: 1) security vulnerability resolved: several bugs after source code review problem description, discussion, solution and upgrade information 2) pending vulnerabilities, solutions, workarounds: - vnc - w3m 3) standard appendix (further information) ______________________________________________________________________________ 1) problem description, brief discussion, solution, upgrade information Hypermail is a tool to convert a Unix mail-box file to a set of cross- referenced HTML documents. During an internal source code review done by Thomas Biege several bugs where found in hypermail and its tools. These bugs allow remote code execution, local tmp race conditions, denial-of-service conditions and read access to files belonging to the host hypermail is running on. Additionally the mail CGI program can be abused by spammers as email- relay and should thus be disabled. There is no temporary fix known other then disabling hypermail. Please download and install the new packages from our FTP servers. 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. Intel i386 Platform: SuSE-8.1: a4b683703b65cb65d0d1b246c2bf652d patch rpm(s): 9e087a97c250c8987dda03da43e0dd1e source rpm(s): 9d95d9872a3ed98a4dbff25e952335d7 SuSE-8.0: 53bdfc3ca1ab0c504f460ac7a18ba42e source rpm(s): be0df42b666fc59e38babd671479d2f1 SuSE-7.3: 81194dcbb3cf149f67eac9948dd79db9 source rpm(s): 9a02ce79e81bab281c418070fa91dbde SuSE-7.2: d61f52df6c995b65e16a4141b1b7efa1 source rpm(s): 66b65eed8f2daefde8115abf77511bba SuSE-7.1: 698338c7d9b8961ec3d4f4ab99ee2436 source rpm(s): 8db31cd4981ee84a0333ec8200443bef Sparc Platform: SuSE-7.3: 341757885457f2e4b018dbb132f1a8f8 source rpm(s): cdc92a18900996524768914c79bf20d9 AXP Alpha Platform: SuSE-7.1: 980f217c12affcb3c0a6d0fd916a5115 source rpm(s): a2242ecc8ba2a13c3d18ca94e6ba23f0 PPC Power PC Platform: SuSE-7.3: 6c7a197fe18a95b7594b2cd7b572837a source rpm(s): e370de5432545f06731c9f841bc84054 SuSE-7.1: 64b3be05678f4789985824e31f8335d2 source rpm(s): 4cd2b65522738594d0b60333f807b8b2 ______________________________________________________________________________ 2) Pending vulnerabilities in SuSE Distributions and Workarounds: - vnc VNC (Virtual Network Computing) uses a weak cookie generation process which can be exploited by an attacker to bypass authentication. New packages are currently being tested and will be available on our FTP servers soon. - w3m The textbased web-browser w3m does not properly escape HTML tags. A malicious HTML page or img alt attribute may lead to information leakage. New packages will be available soon. ______________________________________________________________________________ 3) 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 md5sumafter 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 . - 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-subscribe@suse.com>. 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 <suse-security-announce-subscribe@suse.com>. For general information or the frequently asked questions (faq) send mail to: <suse-security-info@suse.com> or <suse-security-faq@suse.com> respectively. ==================================================================== SuSE's security contact is <security@suse.com> or <security@suse.de>. The <security@suse.de> 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 <security@suse.de> pub 1024D/9C800ACA 2000-10-19 SuSE Package Signing Key <build@suse.de>