diff --git a/crates/smallvec/RUSTSEC-0000-0000.md b/crates/smallvec/RUSTSEC-0000-0000.md
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+```toml
+[advisory]
+id = "RUSTSEC-0000-0000"
+package = "smallvec"
+date = "2021-01-08"
+url = "https://github.com/servo/rust-smallvec/issues/252"
+categories = ["memory-corruption"]
+keywords = ["buffer-overflow", "heap-overflow", "unsound"]
+
+[versions]
+patched = [">= 0.6.14, < 1.0.0", ">= 1.6.1"]
+unaffected = ["< 0.6.3"]
+
+[affected]
+functions = { "smallvec::SmallVec::insert_many" = [">= 0.6.3, < 0.6.14", ">= 1.0.0, < 1.6.1"] }
+```
+
+# Buffer overflow in SmallVec::insert_many
+
+A bug in the `SmallVec::insert_many` method caused it to allocate a buffer that was smaller than needed.  It then wrote past the end of the buffer, causing a buffer overflow and memory corruption on the heap.
+
+This bug was only triggered if the iterator passed to `insert_many` yielded more items than the lower bound returned from its `size_hint` method.
+ 
+The flaw was corrected in smallvec 0.6.14 and 1.6.1, by ensuring that additional space is always reserved for each item inserted.  The fix also simplified the implementation of `insert_many` to use less unsafe code, so it is easier to verify its correctness.
+
+Thank you to Yechan Bae (@Qwaz) and the Rust group at Georgia Tech’s SSLab for finding and reporting this bug.