Both .vbr and .gih files are used in GIMP graphics editors. So if any program is somehow capable of conversion between these two file types it would GIMP. Whenever this conversion is useful, or even possible, could not be reliably verified.
Convert GIMP parametric brush file to GIMP animated brush.
We have found 3 software records in our database eligible for .vbr to .gih file format conversion.
Microsoft Windows software - convert vbr to gih on Windows
A free graphics and photo editor and authoring tool
Convert from vbr file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned vbr to gih. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
Apple macOS / Mac OS X software - convert vbr to gih on OS X
Mac version of the popular graphics editor
Linux/Unix software - convert vbr to gih on Linux
GNU Image Manipulation Program