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+```toml
+[advisory]
+id = "RUSTSEC-0000-0000"
+package = "potato"
+date = "2026-05-02"
+url = "https://github.com/fawdlstty/potato/issues/1"
+informational = "unsound"
+categories = ["memory-corruption"]
+keywords = ["undefined-behavior", "utf-8"]
+
+[versions]
+patched = []
+```
+
+# `RefStr::from_slice()` allows constructing invalid UTF-8 from safe code
+
+`RefStr::from_slice(data, start, len)` is declared safe but uses
+`unsafe { data.get_unchecked(start) }` internally without validating `start`
+and `len`. Callers can construct a `RefStr` pointing to arbitrary bytes.
+
+Combined with `to_str()`, which calls `std::str::from_utf8_unchecked()` on
+the underlying bytes, a caller can produce an invalid `&str` that violates
+Rust's safety requirements. For example, slicing a multi-byte UTF-8 character
+in the middle produces an invalid `&str`.
+
+Both `from_slice()` and `to_str()` are public safe APIs, so this undefined
+behavior can be triggered without writing any `unsafe` code.
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