Not sure where to post this. Baking Soda/superglue turning into yellow flaking mess

I use Superglue and Baking Soda as filler on cracks on some of my props to fill them in. On one prop of mine the combination seems to be going a bit bad as it seeps through the painted layer above it and reveals a yellow flaking mess.

Does anyone know what this is? It doesn't seem to be mold. It seems like some weird reaction going on.