OpenSSH 3.7 Security Advisory: Critical Buffer Fix for SSH Protocol

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Security Changes:
=================

All versions of OpenSSH's sshd prior to 3.7 contain a buffer management error. It is uncertain whether this error is potentially exploitable, however, we prefer to see bugs fixed proactively.

OpenSSH 3.7 fixes this bug.

Changes since OpenSSH 3.6.1:
============================

• The entire OpenSSH code-base has undergone a license review. As a result, all non-ssh1.x code is under a BSD-style license with no advertising requirement. Please refer to README in the source distribution for the exact license terms.
• Rhosts authentication has been removed in ssh(1) and sshd(8).
• Changes in Kerberos support:
  • KerberosV password support now uses a file cache instead of a memory cache.
  • KerberosIV and AFS support has been removed.
  • KerberosV support has been removed from SSH protocol 1.
  • KerberosV password authentication support remains for SSH protocols 1 and 2.
  • This release contains some GSSAPI user authentication support to replace legacy KerberosV authentication support. At present this code is still considered experimental and SHOULD NOT BE USED.
• Changed order that keys are tried in public key authentication. The ssh(1) client tries the keys in the following order:
  1. ssh-agent(1) keys that are found in the ssh_config(5) file
  2. remaining ssh-agent(1) keys
  3. keys that are only listed in the ssh_config(5) file

  This helps when an ssh-agent(1) has many keys, where the sshd(8) server might close the connection before the correct key is tried.

• SOCKS5 support has been added to the dynamic forwarding mode in ssh(1).
• Removed implementation barriers to operation of SSH over SCTP.
• sftp(1) client can now transfer files with quote characters in their filenames.
• Replaced sshd(8)'s VerifyReverseMapping with UseDNS option. When UseDNS option is on, reverse hostname lookups are always performed.
• Fix a number of memory leaks.
• Support for sending tty BREAK over SSH protocol 2.
• Workaround for other vendor bugs in KEX guess handling.
• Support for generating KEX-GEX groups (/etc/moduli) in ssh-keygen(1).
• Automatic re-keying based on amount of data sent over connection.
• New AddressFamily option on client to select protocol to use (IPv4 or IPv6).
• Experimental support for the "aes128-ctr", "aes192-ctr", and "aes256-ctr" ciphers for SSH protocol 2.
• Experimental support for host keys in DNS (draft-ietf-secsh-dns-xx.txt). Please see README.dns in the source distribution for details.

Portable OpenSSH:

• Replace PAM password authentication kludge with a more correct PAM challenge-response module from FreeBSD.
• PAM support may now be enabled/disabled at runtime using the UsePAM directive.
• Many improvements to the OpenSC smartcard support.
• Regression tests now work with portable OpenSSH. Please refer to regress/README.regress in the source distribution.
• On platforms that support it, portable OpenSSH now honors the UMASK, PATH and SUPATH attributes set in /etc/default/login.
• Deny access to locked accounts, regardless of authentication method in use.

Checksums:
==========

• MD5 (openssh-3.7.tgz) = 86864ecc276c5f75b06d4872a553fa70
  
• MD5 (openssh-3.7p1.tar.gz) = 77662801ba2a9cadc0ac10054bc6cb37

Reporting Bugs:
===============

• please read OpenSSH: Problem Reports and Bugzilla Main Page

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