These features are new in beta 0.57 (released 2005-02-20): 
  * Security fixes: two vulnerabilities discovered by iDEFENSE, potentially allowing
    arbitrary code execution on an SFTP client by a malicious SFTP server (but only
    after host key verification), have been fixed. See vuln-sftp-readdir,
    vuln-sftp-string. 
  * Fixed small bug with X forwarding to local displays. 
  * Fixed crashing bug with remote port forwarding. 
  * Fixed handling of SSH2 debug messages (embarrassingly, a bug introduced when
    fixing the previous vulnerability - it was more secure but didn't work any more!). 

These features are new in beta 0.56 (released 2004-10-26): 

  * Security fix: a vulnerability discovered by iDEFENSE (advisory number 10-27-04),
    potentially allowing arbitrary code execution on the client by a malicious SSH2
    server before host key verification, has been fixed. 
  * Ability to restart a session within an inactive window, via a new menu option. 
  * Minimal support for not running a shell or command at all in SSH protocol 2
    (equivalent to OpenSSH's "-N" option). PuTTY/Plink still provide a normal window
    for interaction, and have to be explicitly killed. 
  * Transparent support for CHAP cryptographic authentication in the SOCKS 5 proxy
    protocol. (Not in PuTTYtel.) 
  * More diagnostics in the Event Log, particularly of SSH port forwarding. 
  * Ability to request setting of environment variables in SSH (protocol 2 only).
    (However, we don't know of any servers that support this.) 
  * Ability to send POSIX signals in SSH (protocol 2 only) via the "Special Commands"
    menu. (Again, we don't know of any servers supporting this.) 
  * Bug fix: The PuTTY tools now more consistently support usernames containing
    "@" signs. 
  * Support for the Polish character set "Mazovia". 
  * When logging is enabled, the log file is flushed more frequently, so that its
    contents can be viewed before it is closed. 
  * More flexibility in SSH packet logging: known passwords and session data can be
    omitted from the log file. Passwords are omitted by default. (This option isn'tr
    perfect for removing sensitive details; you should still review log files before
    letting them out of your sight.) 
  * Unix-specific changes: 
    * Ability to set environment variables in pterm. 
    * PuTTY and pterm attempt to use a UTF-8 line character set by default
      if this is indicated by the locale; however, this can be overridden. 

These features are new in beta 0.55 (released 2004-08-03):

  * Security fix: a vulnerability discovered by Core Security Technologies
    (advisory number CORE-2004-0705), potentially allowing arbitrary code
    execution on the client by a malicious server before host key verification,
    has been fixed.
  * Bug fix: General robustness of the SSH1 implementation has been improved,
    which may have fixed further potential security problems although we are
    not aware of any specific ones.
  * Bug fix: Random noise generation was hanging some computers and interfering
    with other processes' precision timing, and should now not do so.
  * Bug fix: dead key support should work better.
  * Bug fix: a terminal speed is now sent to the SSH server.
  * Bug fix: removed a spurious diagnostic message in Plink.
  * Bug fix: the `-load' option in PSCP and PSFTP should work better.
  * Bug fix: X forwarding on the Unix port can now talk to Unix sockets as well
    as TCP sockets.
  * Bug fix: various crashes and assertion failures fixed..

These features were new in beta 0.54 (released 2004-02-12):

  * Port to Unix!
  * Dynamic SSH port forwarding.
  * Ability to leave DNS lookups to the proxy, when using a proxy.
  * Sped up PSFTP.
  * Fixed various bugs, notably one which was impeding port-forwarding of SMB.
  * Some default settings changes: SSH and SSH2 are now default, BCE is off.