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+```toml
+[advisory]
+id = "RUSTSEC-0000-0000"
+package = "fitsrs"
+date = "2024-12-28"
+url = "https://github.com/cds-astro/fitsrs/issues/5"
+references = ["https://github.com/betrusted-io/xous-core/pull/411"]
+categories = []
+keywords = []
+informational = "unsound"
+
+[versions]
+patched = []
+```
+
+# Unsound mutable aliasing to immutable data
+
+There are muliple cases in the codebase, like the [snippet referenced in the issue](https://github.com/cds-astro/fitsrs/blob/5609d8fbb2add2cea207f20ee89117d1f7100b87/src/hdu/data/image.rs#L43-L46), where `unsafe` is used to circumvent aliasing rules.
+
+Immutable inputs are being cast to mutable inputs by using a combination of raw pointers and `UnsafeCell` as intermediate types.
+
+This is undefined behaviour by itself, but in some cases also results in multiple references - some immutable and some mutable - referring to the same input.