diff --git a/crates/arc-swap/RUSTSEC-0000-0000.md b/crates/arc-swap/RUSTSEC-0000-0000.md
new file mode 100644
index 0000000..b9a1f61
--- /dev/null
+++ b/crates/arc-swap/RUSTSEC-0000-0000.md
@@ -0,0 +1,25 @@
+```toml
+[advisory]
+id = "RUSTSEC-0000-0000"
+package = "arc-swap"
+date = "2020-12-10"
+url = "https://github.com/vorner/arc-swap/issues/45"
+categories = ["memory-corruption"]
+keywords = ["dangling reference"]
+
+[versions]
+patched = [">= 1.1.0", ">= 0.4.8"]
+unaffected = ["< 0.4.2"]
+
+[affected]
+functions = { "arc_swap::access::MapGuard::deref" = ["< 1.1.0"] }
+```
+
+# Dangling reference in `access::Map` with Constant
+
+Using the `arc_swap::access::Map` with the `Constant` test helper (or with
+user-provided implementation of the `Access` trait) could sometimes lead to the
+map returning dangling references.
+
+Replaced by implementation without `unsafe`, at the cost of added `Clone` bound
+on the closure and small penalty on performance.