Poppler before 25.04.0 allows crafted input files to trigger out-of-bounds reads in the JBIG2Bitmap::combine function in JBIG2Stream.cc because of a misplaced isOk check.
https://gitlab.freedesktop.org/poppler/poppler/-/merge_requests/1792
https://gitlab.freedesktop.org/poppler/poppler/-/issues/1577