diff --git a/crates/memmap/RUSTSEC-0000-0000.md b/crates/memmap/RUSTSEC-0000-0000.md
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+```toml
+[advisory]
+id = "RUSTSEC-0000-0000"
+package = "memmap"
+date = "2020-12-02"
+url = "https://github.com/danburkert/memmap-rs/issues/90"
+informational = "unmaintained"
+
+[versions]
+patched = []
+unaffected = ["> 0.7.0"]
+```
+
+# memmap is unmaintained
+
+The author of the `memmap` crate is unresponsive.
+
+Maintained alternatives:
+
+- [`mapr`](https://github.com/filecoin-project/mapr)
+- [`memmap2`](https://github.com/RazrFalcon/memmap2-rs)
+