Back in December there started to be some rumblings about a regression introduced in the August 2012 CU (14.0.6126). I first saw it as a question on Stack Exchange. It was reported to me by a couple of other people, so I added it to the August 2012 CU Regressions page. Today a hotfix (also called “Critical On Demand”) patch was released to fix it. Before I tell you how to get it or install it, here are a few things you must know:
It’s based on the December 2012 CU. Install that before you install the COD. Also, DO NOT install the February 2013 CU on top of it. If you think things were bad with just the August 2012 CU installed, you ain’t seen nothing. Installing the February 2013 on top of this will break the crap out of your SharePoint farm. You have been warned.
The download page might show two downloads. Sadly, it’s two versions of the same patch. 
Make sure you download the 14.0.6134.5003 version. It was modified 2/12/2013 at 2:21:26 AM.
Also, promise to read this entire blog post from Joerg Sinemus before you install the hotfix. Promise! You’ll be glad you did.
Okay, now that we’re through all that. You can download the patch here. Here is my full page on it.
Be careful with this patch. Only install it if you’re suffering from the NavNode issue. Being a COD patch it hasn’t been tested as thoroughly as it could be.
Let me know if you have any problems with this.
tk