From wk на gnupg.org  Tue Mar  6 09:02:45 2007
From: wk на gnupg.org (Werner Koch)
Date: Tue, 06 Mar 2007 09:02:45 +0100
Subject: [gnupg-ru] [Announce] Multiple Messages Problem in GnuPG and GPGME
Message-ID: <873b4ibxzu.fsf@wheatstone.g10code.de>

             Multiple Messages Problem in GnuPG and GPGME
            ==============================================
                              2007-03-05


Summary
=======

Gerardo Richarte from Core Security Technologies identified a problem
when using GnuPG in streaming mode.

The problem is actually a variant of a well known problem in the way
signed material is presented in a MUA.  It is possible to insert
additional text before or after a signed (or signed and encrypted)
OpenPGP message and make the user believe that this additional text is
also covered by the signature.  The Core Security advisory describes
several variants of the attack; they all boil down to the fact that it
might not be possible to identify which part of a message is actually
signed if gpg is not used correctly.

[ Please do not send private mail in response to this message.  The
  mailing list gnupg-devel is the best place to discuss this problem
  (please subscribe first so you don't need moderator approval [1]). ]


Impact
======

All applications using GnuPG without properly using the status
interface to verify signed or signed and encrypted messages.

All GPGME versions up to and including 1.1.3.

Starting with version 1.4.7 and 2.0.3, GnuPG implements an additional
and sufficient protection against this common usage problem.

Detached signatures are in no way affected by this problem.


Description
===========

When using gpg (or gpg2) in a pipeline or with redirected input and
output additional data may be inserted into a message.  This allows to
forge a signed message by prefixing it with arbitrary material.  A way
to create such a message is:

  echo "This is my sneaky plaintext message" > foobar.txt
  gpg -z0 --output prefix.gpg --store foobar.txt
  cat prefix.gpg original-signed-message.gpg > forged.gpg

Using gpg naively this results in:

  $ gpg <forged.gpg
  This is my sneaky plaintext message
  Either I'm dead or my watch has stopped.
                  -- Groucho Marx's last words
  gpg: Signature made Mon Feb 26 09:57:04 2007 CET using DSA key ID 68697734
  gpg: Good signature from "Alfa Test (demo key) <alfa на example.net>"
  [...]

and thus gives the impression that the sneaky message is part of the
signed Groucho quote.  The correct way to use gpg with redirection is
by taking care of the status interface:

  $ gpg --status-fd 1 <forged.gpg
  [GNUPG:] PLAINTEXT 62 1172479053 foobar.txt
  [GNUPG:] PLAINTEXT_LENGTH 36
  This is my sneaky plaintext message
  [GNUPG:] PLAINTEXT 62 1172480224 original-signed-message
  [GNUPG:] PLAINTEXT_LENGTH 86
  Either I'm dead or my watch has stopped.
                  -- Groucho Marx's last words
  gpg: Signature made Mon Feb 26 09:57:04 2007 CET using DSA key ID 68697734
  [GNUPG:] SIG_ID UncMPBJYgbG/uszJVNKoCAz+hvY 2007-02-26 1172480224
  [GNUPG:] GOODSIG 2D727CC768697734 Alfa Test (demo key) <alfa на example.net>
  gpg: Good signature from "Alfa Test (demo key) <alfa на example.net>"
  [...]

Here the PLAINTEXT status lines clearly identify the start of a new
message.

Note, that using gpg on the command line is in almost all cases not
done with redirection but by letting gpg save the the signed message.
In this case gpg will save the message to different files or in case
the file names are identical, prompt the over to overwrite the first
one again.

Because the problem of identifying the actual signed content when
mixing the signed data and the signature is very common, the long
standing suggestion for all digital signatures is to use a detached
signature.  A detached signature allows to clearly identify what is
signed and what is the signature.  This is also the reason why
PGP/MIME signed messages are in general to be preferred over the old
style clear signed messages.


Solution
========

Given that there are many applications in use which are subject to the
described problem, we have decided to change GnuPG so that such forged
OpenPGP messages are detected and the signature verification will
fail.  GnuPG 1.4.7 has been released today and is available from the
usual places [2].  If you don't want to update, a minimal patch
against GnuPG 1.4.6 is available at

 ftp://ftp.gnupg.org/gcrypt/gnupg/patches/gnupg-1.4.6-multiple-message.patch

Many applications are using the library GPGME which implements an easy
way to process OpenPGP messages using gpg.  We have updated GPGME to
make it immune against this problem even if an old version of gpg is
being used.  GPGME 1.1.4 is available from the usual places [2].  A
patch (against version 1.1.3 or 1.1.2) is available at

 ftp://ftp.gnupg.org/gcrypt/gpgme/patches/gpgme-1.1.3-multiple-message.patch

Please note that - after applying one of these patches - some
vulnerable applications (mainly MUAs) may fail to handle certain
messages which are composed of several OpenPGP messages.  To continue
the support of such messages fixing the application is required as
there is no way for GnuPG to do it.


Support 
=======

g10 Code GmbH [3], a Duesseldorf based company owned and headed by
GnuPG's principal author, is currently funding GnuPG development.
Support contracts or other financial backing will greatly help us to
improve the quality of GnuPG.


Thanks
======

Gerardo Richarte found this problem.  David Shaw greatly helped to
analyse and describe the core of the problem.




[1] See http://lists.gnupg.org/mailman/listinfo/gnupg-devel
[2] See http://www.gnupg.org/download/ 
[3] See http://www.gnupg.org/service.html
----------- следущая часть -----------
Вложение не в текстовом формате было извлечено&hellip;
Имя     : отсутствует
Тип     : application/pgp-signature
Размер  : 196 байтов
Описание: отсутствует
Url     : /pipermail/attachments/20070306/ce639d51/attachment-0001.pgp 
----------- следущая часть -----------
_______________________________________________
Gnupg-announce mailing list
Gnupg-announce на gnupg.org
http://lists.gnupg.org/mailman/listinfo/gnupg-announce

From wk на gnupg.org  Thu Mar  8 15:36:30 2007
From: wk на gnupg.org (Werner Koch)
Date: Thu, 08 Mar 2007 15:36:30 +0100
Subject: [gnupg-ru] [Announce] GnuPG 2.0.3 released
Message-ID: <87tzwvvm35.fsf@wheatstone.g10code.de>

Hello!
    
We are pleased to announce the availability of a new stable GnuPG-2
release:  Version 2.0.3

This is bug fix release. There are also some minor enhancements.

The GNU Privacy Guard (GnuPG) is GNU's tool for secure communication
and data storage.  It can be used to encrypt data, create digital
signatures, help authenticating using Secure Shell and to provide a
framework for public key cryptography.  It includes an advanced key
management facility and is compliant with the OpenPGP and S/MIME
standards.

GnuPG-2 has a different architecture than GnuPG-1 (e.g. 1.4.6) in that
it splits up functionality into several modules.  However, both
versions may be installed alongside without any conflict.  In fact,
the gpg version from GnuPG-1 is able to make use of the gpg-agent as
included in GnuPG-2 and allows for seamless passphrase caching.  The
advantage of GnuPG-1 is its smaller size and the lack of dependency on
other modules at run and build time.  We will keep maintaining GnuPG-1
versions because they are very useful for small systems and for server
based applications requiring only OpenPGP support.

GnuPG is distributed under the terms of the GNU General Public License
(GPL).  GnuPG-2 works best on GNU/Linux or *BSD systems. 


Getting the Software
====================

Please follow the instructions found at http://www.gnupg.org/download/
or read on:

GnuPG 2.0.3 may be downloaded from one of the GnuPG mirror sites or
direct from ftp://ftp.gnupg.org/gcrypt/gnupg/ .  The list of mirrors
can be found at http://www.gnupg.org/mirrors.html .  Note, that GnuPG
is not available at ftp.gnu.org.

On the FTP server and ist mirrors you should find the following files
in the *gnupg* directory:

  gnupg-2.0.3.tar.bz2 (3.8M)
  gnupg-2.0.3.tar.bz2.sig

      GnuPG source compressed using BZIP2 and OpenPGP signature.

  gnupg-2.0.3-2.0.3.diff.bz2 (29k)

      A patch file to upgrade a 2.0.2 GnuPG source.  The patch file
      does not include updates of the language files.

Note, that we don't distribute gzip compressed tarballs.  


Checking the Integrity
======================

In order to check that the version of GnuPG which you are going to
install is an original and unmodified one, you can do it in one of
the following ways:

 * If you already have a trusted version of GnuPG installed, you
   can simply check the supplied signature.  For example to check the
   signature of the file gnupg-2.0.3.tar.bz2 you would use this command:

     gpg --verify gnupg-2.0.3.tar.bz2.sig

   This checks whether the signature file matches the source file.
   You should see a message indicating that the signature is good and
   made by that signing key.  Make sure that you have the right key,
   either by checking the fingerprint of that key with other sources
   or by checking that the key has been signed by a trustworthy other
   key.  Note, that you can retrieve the signing key using the command

     finger wk ,at' g10code.com

   or using a keyserver like

     gpg --recv-key 1CE0C630

   The distribution key 1CE0C630 is signed by the well known key
   5B0358A2.  If you get an key expired message, you should retrieve a
   fresh copy as the expiration date might have been prolonged.

   NEVER USE A GNUPG VERSION YOU JUST DOWNLOADED TO CHECK THE
   INTEGRITY OF THE SOURCE - USE AN EXISTING GNUPG INSTALLATION!

 * If you are not able to use an old version of GnuPG, you have to verify
   the SHA-1 checksum.  Assuming you downloaded the file
   gnupg-2.0.3.tar.bz2, you would run the sha1sum command like this:

     sha1sum gnupg-2.0.3.tar.bz2

   and check that the output matches the first line from the
   following list:

4680bcb96873191b331252ae40b35e39589c58ca  gnupg-2.0.3.tar.bz2
901b8d9fe430e12c14d16365a08d50389c305f9a  gnupg-2.0.2-2.0.3.diff.bz2



What's New
===========

 * By default, do not allow processing multiple plaintexts in a single
   stream.  Many programs that called GnuPG were assuming that GnuPG
   did not permit this, and were thus not using the plaintext boundary
   status tags that GnuPG provides.  This change makes GnuPG reject
   such messages by default which makes those programs safe again.
   --allow-multiple-messages returns to the old behavior.

 * New --verify-option show-primary-uid-only. 

 * gpgconf may now reads a global configuration file to select which
   options are changeable by a frontend.  The new applygnupgdefaults
   tool may be used by an admin to set default options for all users.

 * The PIN pad of the Cherry XX44 keyboard is now supported.  The
   DINSIG and the NKS applications are now also aware of PIN pads.


Internationalization
====================

GnuPG comes with support for 27 languages.  Due to a lot of new and
changed strings most translations are not entirely complete.  The
Swedish, Turkish, German and Russian translations should be complete.


Documentation
=============

We are currently working on an installation guide to explain in more
detail how to configure the new features.  As of now the chapters on
gpg-agent and gpgsm include brief information on how to set up the
whole thing.  Please watch the GnuPG website for updates of the
documentation.  In the meantime you may search the GnuPG mailing list
archives or ask on the gnupg-users mailing lists for advise on how to
solve problems.  Many of the new features are around for several years
and thus enough public knowledge is already available.  KDE's KMail is
the most prominent user of GnuPG.  In fact it has been developed along
with the Kmail folks.  Mutt users might want to use the configure
option "--enable-gpgme" and "set use_crypt_gpgme" in ~/.muttrc to make
use of GnuPG-2 to enable S/MIME in addition to a reworked OpenPGP
support.

The manual is also available online in HTML format at
  http://www.gnupg.org/documentation/manuals/gnupg/ 
and as an PDF at
  http://www.gnupg.org/documentation/manuals/gnupg.pdf .


Support
=======

Improving GnuPG is costly, but you can help!  We are looking for
organizations that find GnuPG useful and wish to contribute back.  You
can contribute by reporting bugs, improve the software, or by donating
money.

Commercial support contracts for GnuPG are available, and they help
finance continued maintenance.  g10 Code GmbH, a Duesseldorf based
company owned and headed by GnuPG's principal author, is currently
funding GnuPG development.  We are always looking for interesting
development projects.

A service directory is available at:

  http://www.gnupg.org/service.html


Thanks
======

We have to thank all the people who helped with this release, be it
testing, coding, translating, suggesting, auditing, administering the
servers, spreading the word or answering questions on the mailing
lists.  


Happy Hacking,

  The GnuPG Team (David, Marcus, Werner and all other contributors)


-- 
Werner Koch                                      <wk на gnupg.org>
The GnuPG Experts                                http://g10code.com
----------- следущая часть -----------
Вложение не в текстовом формате было извлечено&hellip;
Имя     : отсутствует
Тип     : application/pgp-signature
Размер  : 196 байтов
Описание: отсутствует
Url     : /pipermail/attachments/20070308/12872c7f/attachment.pgp 
----------- следущая часть -----------
_______________________________________________
Gnupg-announce mailing list
Gnupg-announce на gnupg.org
http://lists.gnupg.org/mailman/listinfo/gnupg-announce