===================================================================== CERT-Renater Note d'Information No. 2005/VULN104 _____________________________________________________________________ DATE : 22/02/2005 HARDWARE PLATFORM(S) : / OPERATING SYSTEM(S) : Systems running squid. ====================================================================== ______________________________________________________________________________ SUSE Security Announcement Package: squid Announcement-ID: SUSE-SA:2005:008 Date: Tue, Feb 22nd 2005 14:30:00 MEST Affected products: 8.2, 9.0, 9.1, 9.2 SUSE Linux Enterprise Server 8, 9 Vulnerability Type: remote denial of service Severity (1-10): 4 SUSE default package: no Cross References: CAN-2005-0446 Content of this advisory: 1) security vulnerability resolved: remote denial of service attack 2) solution/workaround 3) special instructions and notes 4) package location and checksums 5) pending vulnerabilities, solutions, workarounds: none 6) standard appendix (further information) ______________________________________________________________________________ 1) problem description, brief discussion Squid is an Open Source web proxy. A remote attacker was potentially able to crash the Squid web proxy if the log_fqdn option was set to "on" and the DNS replies were manipulated. This is tracked by the Mitre CVE ID CAN-2005-0446. This update also fixes a defect in the last security update patch (CAN-2005-0241). 2) solution/workaround Install the fixed packages. 3) special instructions and notes Restart the proxy using /etc/init.d/squid try-restart 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/squid-2.5.STABLE6-6.8.i586.rpm a207ddd1b3700d2a345570b40ffdcb16 SUSE Linux 9.1: ftp://ftp.suse.com/pub/suse/i386/update/9.1/rpm/i586/squid-2.5.STABLE5-42.30.i586.rpm 8b3f3300e055260ea5a59c8a95f71d42 SUSE Linux 9.0: ftp://ftp.suse.com/pub/suse/i386/update/9.0/rpm/i586/squid-2.5.STABLE3-120.i586.rpm 482d3c270c8186d7c4b68d72a50143cc SUSE Linux 8.2: ftp://ftp.suse.com/pub/suse/i386/update/8.2/rpm/i586/squid-2.5.STABLE1-108.i586.rpm 368d091defd189209c0786ac337b92f3 x86-64 Platform: SUSE Linux 9.2: ftp://ftp.suse.com/pub/suse/i386/update/9.2/rpm/x86_64/squid-2.5.STABLE6-6.8.x86_64.rpm a1efed588e24a63ff5af8db9a0230c23 source rpm(s): ftp://ftp.suse.com/pub/suse/i386/update/9.2/rpm/src/squid-2.5.STABLE6-6.8.src.rpm 404c028061fe715b56454a072070f962 SUSE Linux 9.1: ftp://ftp.suse.com/pub/suse/x86_64/update/9.1/rpm/x86_64/squid-2.5.STABLE5-42.30.x86_64.rpm 78c20bf8fcbb4c07e576d92e6cdaedb4 source rpm(s): ftp://ftp.suse.com/pub/suse/x86_64/update/9.1/rpm/src/squid-2.5.STABLE5-42.30.src.rpm dc8b23cb96e39ea679a07216429e1a72 SUSE Linux 9.0: ftp://ftp.suse.com/pub/suse/x86_64/update/9.0/rpm/x86_64/squid-2.5.STABLE3-120.x86_64.rpm b59f02f04ed720bb56fae0e713f6fcbf source rpm(s): ftp://ftp.suse.com/pub/suse/x86_64/update/9.0/rpm/src/squid-2.5.STABLE3-120.src.rpm 4a9072581af98dfc76eaf3c44c88813a ______________________________________________________________________________ 5) Pending vulnerabilities in SUSE Distributions and Workarounds: See the 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 + =========================================================