diff --git a/crates/sm-ext-rs/RUSTSEC-0000-0000.md b/crates/sm-ext-rs/RUSTSEC-0000-0000.md
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+```toml
+[advisory]
+id = "RUSTSEC-0000-0000"
+package = "sm-ext-rs"
+date = "2026-01-30"
+url = "https://github.com/asherkin/sm-ext-rs/issues/2"
+informational = "unmaintained"
+
+[versions]
+patched = []
+```
+
+# sm-ext-rs is unmaintained
+
+sm-ext-rs will no longer be maintained as the last commit was 7 years ago. The project has an unsoundness issue, which can further lead to a memory safety bug as in [issue #2](https://github.com/asherkin/sm-ext-rs/issues/2).
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