Underneath our vanity, the back portion has separated from the right side causing the drawer to come apart as well. The wall is too far back to connect it to anything. I feel like there has to be something that can just jerry rig it for a rough and cheap repair. My concern is I'm going to have to redo the whole vanity, which we can't afford. I've attached photos which should provide a better explanation.
It's either poor quality, or badly stressed by not sitting on the floor properly to support it, or both. You should look for and address improper floor support to have the repair attempt last.
I suppose if you wanted to bodge a steel angle bracket in there that might make a crude fix, but how well screws will hold in whatever sort of not-quite-wood it's apparently made from is unknown.
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