Comment by john01dav
21 hours ago
That might be challenging because you can trivially determine the output file sized based on the dimensions in pixels and pixel format, so if the DEFLATE stream goes beyond that you can stop decoding and discard the image as malformed. Of course, some decoders may not do so and thus would be vulnerable.
Is it a problem through ? I'm pretty sure that any check is on the weight of the PNG, not the actual dimension of the image.
PNG doesn't have size limitation on the image dimensions (4bytes each). So I bet you can break at least one scrap bot with that.