From security@TURBOLINUX.COM Thu Feb 22 18:40:14 2001 From: security@TURBOLINUX.COM To: BUGTRAQ@SECURITYFOCUS.COM Date: Thu, 22 Feb 2001 14:11:43 -0800 Subject: [BUGTRAQ] [TL-Security-Announce] Bind-8.2.3-2 TLSA2001004-1 ___________________________________________________________________________ TurboLinux Security Announcement Package: Bind Vulnerable Packages: All versions previous to 8.2.3 Date: 02/21/2001 5:00 PDT Affected TurboLinux versions:TL 6.1 WorkStation, All TurboLinux versions 6.0.5 and earlier TurboLinux Advisory ID#: TLSA2001004-1 Credits: Vulnerabilities discovered by the COVERT Labs at PGP Security and Claudio Musmarra. Also, special thanks to Andrew Cameron for sending an email notifying us of this issue. ___________________________________________________________________________ Two vulnerabilities have been discovered in ISC BIND 8. Please update the packages in your installation as soon as possible. ___________________________________________________________________________ 1. Problem Summary(From the CERT/CC, CERT Advisory CA-2001-02) A. ISC BIND 8 contains a buffer overflow in transaction signature (TSIG) handling code. During the processing of a transaction signature (TSIG), BIND 8 checks for the presence of TSIGs that fail to include a valid key. If such a TSIG is found, BIND skips normal processing of the request and jumps directly to code designed to send an error response. Because the error- handling code initializes variables differently than in normal processing it invalidates the assumptions that later function calls make about the size of the request buffer. Once these assumptions are invalidated, the code that adds a new (valid) signature to the responses may overflow the request buffer and overwrite adjacent memory on the stack or the heap. When combined with other buffer overflow exploitation techniques, an attacker can gain unauthorized privileged access to the system, allowing the execution of arbitrary code. B. Queries to ISC BIND servers may disclose environment variables This vulnerability is an information leak in the query processing code of BIND 8 that allows a remote attacker to access the program stack, possibly exposing program and/or environment variables. This vulnerability is triggered by sending a specially formatted query to vulnerable BIND servers. 2. Impact(From CERT/CC, CERT Advisory CA-2001-02) A. ISC BIND 8 contains buffer overflow in transaction signature (TSIG) handling code This vulnerability may allow an attacker to execute code with the same privileges as the BIND server. Because BIND is typically run by a superuser account, the execution would occur with superuser privileges. B. Queries to ISC BIND servers may disclose environment variables This vulnerability may allow attackers to read information from the program stack, possibly exposing environment variables. 3. Solution Update each package from our ftp server by running the following command: rpm -Uvh ftp_path_to_filename Where ftp_path_to_filename is the following: ftp://ftp.turbolinux.com/pub/updates/6.0/security/bind-8.2.3-2.i386.rpm ftp://ftp.turbolinux.com/pub/updates/6.0/security/bind-contrib-8.2.3-2.i386.rpm ftp://ftp.turbolinux.com/pub/updates/6.0/security/bind-devel-8.2.3-2.i386.rpm ftp://ftp.turbolinux.com/pub/updates/6.0/security/bind-utils-8.2.3-2.i386.rpm The source RPM can be downloaded here: ftp://ftp.turbolinux.com/pub/updates/6.0/SRPMS/bind-8.2.3-2.src.rpm **Note: You must rebuild and install the RPM if you choose to download and install the SRPM. Simply installing the SRPM alone WILL NOT CLOSE THE SECURITY HOLE. Please verify the MD5 checksums of the updates before you install: MD5 sum Package Name --------------------------------------------------------------------------- dec967e3a1dd16bdcca0c6fe6e9114d6 bind-8.2.3-2.i386.rpm 2e84bbbcd6a09d7c5060dd01480ff3de bind-contrib-8.2.3-2.i386.rpm 06612093126372f8d618ea842fd402ec bind-devel-8.2.3-2.i386.rpm 3f390ce4d1b7ceaa477df62cc3fe3174 bind-utils-8.2.3-2.i386.rpm 25c701c7158af3f773d1a478c8872d05 bind-8.2.3-2.src.rpm ___________________________________________________________________________ These packages are GPG signed by TurboLinux for security. Our key is available here: http://www.turbolinux.com/security/tlgpgkey.asc To verify a package, use the following command: rpm --checksig name_of_rpm To examine only the md5sum, use the following command: rpm --checksig --nogpg name_of_rpm **Note: Checking GPG keys requires RPM 3.0 or higher. ___________________________________________________________________________ You can find more updates on our ftp server: ftp://ftp.turbolinux.com/pub/updates/6.0/security/ for TL6.0 Workstation and Server security updates ftp://ftp.turbolinux.com/pub/updates/4.0/security/ for TL4.0 Workstation and Server security updates Our webpage for security announcements: http://www.turbolinux.com/security If you want to report vulnerabilities, please contact: security@turbolinux.com ___________________________________________________________________________ Subscribe to the TurboLinux Security Mailing lists: TL-security - A moderated list for discussing security issues TurboLinux products. Subscribe at http://www.turbolinux.com/mailman/listinfo/tl-security TL-security-announce - An announce-only mailing list for security updates and alerts. Subscribe at: http://www.turbolinux.com/mailman/listinfo/tl-security-announce [Part 2, Application/PGP-SIGNATURE 240bytes] [Unable to print this part]