[LWN Logo]
[LWN.net]
From: security@turbolinux.com
Date: Thu, 22 Feb 2001 14:11:43 -0800
To: tl-security-announce@www1.turbolinux.com
Subject: [TL-Security-Announce] Bind-8.2.3-2 TLSA2001004-1


--tjCHc7DPkfUGtrlw
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline



___________________________________________________________________________

                     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<apcameron@hotmail.com> 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

--tjCHc7DPkfUGtrlw
Content-Type: application/pgp-signature
Content-Disposition: inline

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.0.2 (GNU/Linux)
Comment: For info see http://www.gnupg.org

iD8DBQE6lY6f7eR7bnHQKeQRAvYrAJ9cP8JsknHbmgo5VTY5qSNDcC77ywCfRnGk
jxj25p6onDgpMuF5oYK2W/s=
=r+Jy
-----END PGP SIGNATURE-----

--tjCHc7DPkfUGtrlw--


_______________________________________________
TL-Security-Announce mailing list
TL-Security-Announce@www.turbolinux.com
http://www.turbolinux.com/mailman/listinfo/tl-security-announce