Theoretically I think you could exploit this by creating a directory with a path string longer than MAX_PATH and then starting a Firefox instance with that path as its working directory, and then you'd get the stack overflow the next time an update runs. I'm not sure how feasible that procedure is.
Bug 1577061 Comment 5 Edit History
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Theoretically I think you could exploit this by creating a directory with a path string longer than MAX_PATH and then starting a Firefox instance with that path as its working directory, and then you'd get the stack buffer overrun the next time an update runs. I'm not sure how feasible that procedure is.