diff --git a/crates/obstack/RUSTSEC-0000-0000.toml b/crates/obstack/RUSTSEC-0000-0000.toml
new file mode 100644
index 0000000..7d8b5e0
--- /dev/null
+++ b/crates/obstack/RUSTSEC-0000-0000.toml
@@ -0,0 +1,13 @@
+[advisory]
+id = "RUSTSEC-0000-0000"
+package = "obstack"
+date = "2020-09-03"
+informational = "unsound"
+title = "Obstack generates unaligned references"
+url = "https://github.com/petertodd/rust-obstack/issues/4"
+description = """
+Obstack generates unaligned references for types that require a large alignment.
+"""
+
+[versions]
+patched = []