Log Message:
putty: Update to 0.74

Changelog:
This release fixes the following security issues:

 - In some situations an SSH server could cause PuTTY to access freed
   mdmory by pretending to accept an SSH key and then refusing the
   actual signature. It can only happen if you're using an SSH agent.

 - New configuration option to disable PuTTY's default policy of
   changing its host key algorithm preferences to prefer keys it
   already knows. (There is a theoretical information leak in this
   policy.)

Other bug fixes include:

 - Windows installer: the text in the installer UI is now visible in
   Windows high-contrast mode. (Previously it was white on white by
   mistake.)

 - Windows 7: fixed spurious OS out-of-memory error when reading
   passwords from a Windows console (e.g. psftp).

 - Terminal crash: the dreaded "line==NULL" error could happen if an
   application switched between the main and alternate screens while
   the user was looking at the scrollback.

 - Terminal crash: the terminal could fail an assertion when sending
   an empty answerback string, and when pasting text none of whose
   characters exist in the selected character set.

 - SSH: fixed endless memory-allocating loop that could be triggered
   by the combination of a misbehaving SSH agent and PuTTY's bug
   compatibility mode for padded RSA signatures.

 - File transfer: when uploading files to some SFTP servers (e.g. the
   one in proftpd's mod_sftp), PSFTP would consume up to 4GB of local
   memory before sending anything to the server.

 - Terminal behaviour: sometimes the cursor was put in the wrong place
   after restoring from the alternate screen.

 - GTK: fixed font size calculation when using newer Pango libraries
   (e.g. the one on Ubuntu 20.04).

 - GTK: scroll wheel events now work in unusual environments like VNC.