diff --git a/crates/comrak/RUSTSEC-0000-0000.md b/crates/comrak/RUSTSEC-0000-0000.md
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+```toml
+[advisory]
+id = "RUSTSEC-0000-0000"
+package = "comrak"
+date = "2021-02-21"
+url = "https://github.com/kivikakk/comrak/releases/tag/0.9.1"
+categories = ["format-injection"]
+keywords = ["xss"]
+
+[versions]
+patched = [">= 0.9.1"]
+```
+
+# XSS in `comrak`
+
+The [comrak](https://github.com/kivikakk/comrak) we were matching unsafe URL prefixes, such as `data:` or `javascript:` , in a case-sensitive manner. This meant prefixes like `Data:` were untouched.
+