Nagios Core 3.4.3 was just released and can be grabbed from the downloads page. The Changelog can be found here. This release is essentially the 3.4.2 minus the changes intended for Nagios 4 that had slipped into the code. Thanks to Mike Guthrie, Eric Stanley, and Phil Randal for their contributions and to Phil Randal and Dan Wittenberg for their testing and feedback on the release candidates.