CVE-2026-84449 libheif hOp_RGB24_32_to_YCbCr Memory Access Error / SEGV

libheif is a HEIF and AVIF file format decoder and encoder. Prior to 1.19.6, OpRGB2432toYCbCr::convertcolorspace stores image-plane strides in an integer width that can overflow for extremely large RGB images created through heifimagecreate and heifimageaddplane. The resulting wrapped stride caus...