libheif 1.4.0 has a use-after-free in heif::HeifContext::Image::set_alpha_channel in heif_context.h because heif_context.cc mishandles references to non-existing alpha images.

There is a vulnerability in the strided image data parsing code in the emscripten wrapper for libheif. An attacker could exploit this through a crafted image file to cause a buffer overflow in linear memory during a memcpy call.