png_image_free in png.c in libpng 1.6.x before 1.6.37 has a use-after-free because png_image_free_function is called under png_safe_execute.

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DEBIAN-CVE-2019-7317

pngimagefree in png.c in libpng 1.6.x before 1.6.37 has a use-after-free because pngimagefreefunction is called under pngsafeexecute...