libheif is a HEIF and AVIF file format decoder and encoder. Versions prior to 1.22.0 crashes in the public C API heif image handle get image tiling() when a malformed uncompressed HEIF image item has an associated uncC property but no associated ispe property. In debug builds this trips the ispe && uncC assertion in ImageItem uncompressed::get heif image tiling(). In a release/NDEBUG ASan build, the same file causes a null pointer read at address 0xa8. Version 1.22.0 fixes the issue.