Transitively it gets 0.1.53 from groovy-ssh library, and there is latest version 0.1.54, from the change log it seems like there are few bug fixes and enhancements which would benefit this plugin for sure.

http://www.jcraft.com/jsch/ChangeLog

And Few other minor things I noticed, doesn't need to addressed with this pull request but it would be nice as these are small changes:

• Include the step name in the DisplayName for all the steps, so that these will look okay in blue ocean.
• Add a log statement for sshScript step to mention which script being executed as actual log message from groovy ssh doesn't print the file name.