Wt 4.9.2 is a small patch release that fixes a couple of issues. Check the release notes for more info.
Here are the links:
Wt 4.9.2 (C++): download wt-4.9.2.tar.gz (release notes)
JWt 4.9.2 (Java): download jwt-4.9.2.zip (release notes)
Binary builds for Windows are available on the GitHub releases page.