As I knew that FileZilla used PuTTY I just wanted to mention that PuTTY 0.56 was just released to fix a security issue and a few other minor things.
http://www.chiark.greenend.org.uk/~sgtatham/putty/
This is not mentioned on the main page, but is mentioned on download and Wishlist pages.
* Security vulnerabilities
o vuln-ssh2-debug: Vulnerability: crafted SSH2_MSG_DEBUG can cause remote code execution
* Bugs (and semi-bugs)
o ampersat-in-username: Allow @ sign in username
o log-flush: Flush session log file during session
* Wishes
o mazovia: Support for Mazovia character set
o socks5-chap: CHAP authentication support for SOCKS5
o reuse-windows: Ability to re-use dead session windows
o ssh-log-pw-blank: Blank known passwords by default in SSH packet log
o ssh2-env-var: Support setting environment variables in SSH-2
PuTTY Update 0.56
Moderator: Project members