[OpenPKG-SA-2003.013] OpenPKG Security Advisory (openssl)

[OpenPKG <openpkg () openpkg org>]

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OpenPKG Security Advisory                            The OpenPKG Project
http://www.openpkg.org/security.html              http://www.openpkg.org
openpkg-security () openpkg org                         openpkg () openpkg org
OpenPKG-SA-2003.013                                          19-Feb-2003
________________________________________________________________________

Package:             openssl
Vulnerability:       obtain plaintext of SSL/TLS communication
OpenPKG Specific:    no

Affected Releases:   Affected Packages:        Corrected Packages:
OpenPKG CURRENT      <= openssl-0.9.7-20030111 >= openssl-0.9.7a-20030219
OpenPKG 1.2          <= openssl-0.9.7-1.2.0    >= openssl-0.9.7-1.2.1
OpenPKG 1.1          <= openssl-0.9.6g-1.1.0   >= openssl-0.9.6g-1.1.1

Affected Releases:   Dependent Packages:

OpenPKG CURRENT      apache cadaver cpu curl dsniff easysoap ethereal
                     exim fetchmail imap imapd inn linc links lynx mico
                     mixmaster mozilla mutt nail neon openldap openvpn
                     perl-ssl postfix postgresql qpopper samba sendmail
                     siege sio sitecopy socat stunnel subversion sysmon
                     w3m wget

OpenPKG 1.2          apache cpu curl ethereal fetchmail imap inn
                     links lynx mico mutt nail neon openldap perl-ssl
                     postfix postgresql qpopper samba sendmail siege
                     sitecopy socat stunnel sysmon w3m wget

OpenPKG 1.1          apache curl fetchmail inn links lynx mutt neon
                     openldap perl-ssl postfix postgresql qpopper samba
                     siege sitecopy socat stunnel sysmon w3m

Description:
  In an upcoming CRYPTO 2003 paper, Brice Canvel (EPFL), Alain
  Hiltgen (UBS), Serge Vaudenay (EPFL), and Martin Vuagnoux (EPFL,
  Ilion) describe and demonstrate a timing-based attack on SSL/TLS
  with CBC ciphersuites. According to an OpenSSL security advisory
  [0], the OpenSSL implementation is vulnerable to this attack. The
  Common Vulnerabilities and Exposures (CVE) project assigned the id
  CAN-2003-0078 [2] to the problem.

  The attack assumes that multiple SSL/TLS connections involve a common
  fixed plaintext block, such as a password. An active attacker can
  substitute specifically made-up ciphertext blocks for blocks sent
  by legitimate SSL/TLS parties and measure the time until a response
  arrives. SSL/TLS includes data authentication to ensure that such
  modified ciphertext blocks will be rejected by the peer (and the
  connection aborted), but the attacker may be able to use timing
  observations to distinguish between two different error cases, namely
  block cipher padding errors and MAC verification errors.

  This is sufficient for an adaptive attack that finally can obtain the
  complete plaintext block. Although this cannot be easily exploited,
  because the attack requires the ability to be a man-in-the-middle,
  repeated communications that have a common plaintext block, decoding
  failures not signaling problems on the client and server side, and
  a network between the attacker and the server sufficient enough to
  reasonably observe timing differences.

  OpenSSL version since 0.9.6c supposedly treat block cipher padding
  errors like MAC verification errors during record decryption [1], but
  MAC verification was still skipped after detection of a padding error,
  which allowed the timing attack.

  Please check whether you are affected by running "<prefix>/bin/rpm -q
  openssl". If you have the "openssl" package installed and its version
  is affected (see above), we recommend that you immediately upgrade it
  (see Solution) and it's dependent packages (see above), if any, too.
  [3][4]

Solution:
  Select the updated source RPM appropriate for your OpenPKG release
  [5][6], fetch it from the OpenPKG FTP service [7][8] or a mirror
  location, verify its integrity [9], build a corresponding binary RPM
  from it [3] and update your OpenPKG installation by applying the binary
  RPM [4]. For the current release OpenPKG 1.2, perform the following
  operations to permanently fix the security problem (for other releases
  adjust accordingly).

  $ ftp ftp.openpkg.org
  ftp> bin
  ftp> cd release/1.2/UPD
  ftp> get openssl-0.9.7-1.2.1.src.rpm
  ftp> bye
  $ <prefix>/bin/rpm -v --checksig openssl-0.9.7-1.2.1.src.rpm
  $ <prefix>/bin/rpm --rebuild openssl-0.9.7-1.2.1.src.rpm
  $ su -
  # <prefix>/bin/rpm -Fvh <prefix>/RPM/PKG/openssl-0.9.7-1.2.1.*.rpm

  Additionally, we recommend that you rebuild and reinstall
  all dependent packages (see above), if any, too. [3][4]
________________________________________________________________________

References:
  [0] http://www.openssl.org/news/secadv_20030219.txt
  [1] http://www.openssl.org/~bodo/tls-cbc.txt
  [2] http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2003-0078
  [3] http://www.openpkg.org/tutorial.html#regular-source
  [4] http://www.openpkg.org/tutorial.html#regular-binary
  [5] ftp://ftp.openpkg.org/release/1.1/UPD/openssl-0.9.6g-1.1.1.src.rpm
  [6] ftp://ftp.openpkg.org/release/1.2/UPD/openssl-0.9.7-1.2.1.src.rpm
  [7] ftp://ftp.openpkg.org/release/1.1/UPD/
  [8] ftp://ftp.openpkg.org/release/1.2/UPD/
  [9] http://www.openpkg.org/security.html#signature
________________________________________________________________________

For security reasons, this advisory was digitally signed with
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of the OpenPKG project which you can find under the official URL
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________________________________________________________________________

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