From security@PROGENY.COM Thu Apr 19 00:05:53 2001 From: Progeny Security Team To: BUGTRAQ@SECURITYFOCUS.COM Date: Wed, 18 Apr 2001 13:03:54 -0500 Subject: [BUGTRAQ] PROGENY-SA-2001-05: Samba /tmp vulnerabilities -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 --------------------------------------------------------------------------- PROGENY LINUX SYSTEMS -- SECURITY ADVISORY PROGENY-SA-2001-05 --------------------------------------------------------------------------- Topic: Samba /tmp vulnerabilities Category: net Modules: samba smbclient Announced: 2001-04-18 Credits: Marcus Meissner Affects: Progeny Debian (samba, smbclient prior to 2.0.7-3.2) Debian GNU/Linux (samba, smbclient prior to 2.0.7-3.2) Vendor-Status: New Version Released (samba_2.0.7-3.2, smbclient_2.0.7-3.2) Corrected: 2001-04-18 Progeny Only: NO $Id: PROGENY-SA-2001-05,v 1.11 2001/04/18 17:53:55 jdaily Exp $ --------------------------------------------------------------------------- SYNOPSIS smbclient and samba use /tmp files in an insecure manner, allowing local users to overwrite files to which they would ordinarily not have access. PROBLEM DESCRIPTION Marcus Meissner discovered that Samba was not creating temporary files safely. This happened in two places: * When a remote user queried a printer queue, samba would create a temporary file in which the queue's data would be written. This was using a predictable filename, and doing it insecurely, allowing a local attacker to trick samba into overwriting files it shouldn't. * The smbclient "more" and "mput" commands also created temporary files in /tmp insecurely. Both problems have been fixed in version 2.0.7-3.2. We recommend that you upgrade your samba package immediately. IMPACT Local users can overwrite system files, causing corruption and potentially gaining root access. SOLUTION Upgrade to a fixed version of samba. Samba versions 2.0.8 and 2.2.0 correct the problem. For your convenience, you may upgrade to the packages smbclient_2.0.7-3.2, samba-common_2.0.7-3.2, and samba_2.0.7-3.2. WORKAROUND No known workaround exists for this vulnerability. UPDATING VIA APT-GET 1. Ensure that your /etc/apt/sources.list file has a URI for Progeny's update repository: deb http://archive.progeny.com/progeny updates/newton/ 2. Update your cache of available packages for apt(8). Example: # apt-get update 3. Using apt(8), install the new package. apt(8) will download the update, verify its integrity with md5, and then install the package on your system with dpkg(8). Example: # apt-get install samba smbclient UPDATING VIA DPKG 1. Using your preferred FTP/HTTP client to retrieve the following updated files from Progeny's update archive at: http://archive.progeny.com/progeny/updates/newton/ Filename MD5 Checksum ------------------------------------ -------------------------------- samba-common_2.0.7-3.2_i386.deb 7eabad23b6c221ec3cb50e6b41a7de99 samba_2.0.7-3.2_i386.deb 36fbb1a508503bc9c0844b5f98f98264 smbclient_2.0.7-3.2_i386.deb fe8c68a7cf5499e2b665e5ac73aad3ac Example: # wget \ http://archive.progeny.com/progeny/updates/newton/samba-common_2.0.7-3.2_i386.deb \ http://archive.progeny.com/progeny/updates/newton/samba_2.0.7-3.2_i386.deb \ http://archive.progeny.com/progeny/updates/newton/smbclient_2.0.7-3.2_i386.deb 2. Use the md5sum command on the retrieved files to verify that they match the md5sum provided in this advisory: Example: # md5sum samba-common_2.0.7-3.2_i386.deb 3. Then install the replacement package(s) using the dpkg command. Example: # dpkg --install samba-common_2.0.7-3.2_i386.deb \ samba_2.0.7-3.2_i386.deb smbclient_2.0.7-3.2_i386.deb --------------------------------------------------------------------------- pub 1024D/F92D4D1F 2001-04-04 Progeny Security Team -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.4 (GNU/Linux) Comment: For info see http://www.gnupg.org iEYEARECAAYFAjrd1LoACgkQScF9I/ktTR9OWACfejd5JYdQVRKIXP01na06y8F/ 9vYAnA5yFCQ9oFbdW9TuhtaqYRbDOYBa =n/Ha -----END PGP SIGNATURE-----