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+```toml
+[advisory]
+id = "RUSTSEC-0000-0000"
+package = "hyper"
+date = "2021-02-05"
+url = "https://github.com/hyperium/hyper/security/advisories/GHSA-6hfq-h8hq-87mf"
+categories = ["format-injection"]
+keywords = ["http", "request-smuggling"]
+aliases = ["CVE-2021-21299"]
+
+[versions]
+patched = [">= 0.14.3", "0.13.10"]
+unaffected = ["< 0.12.0"]
+```
+
+# Multiple Transfer-Encoding headers misinterprets request payload
+
+hyper's HTTP server code had a flaw that incorrectly understands some requests
+with multiple transfer-encoding headers to have a chunked payload, when it
+should have been rejected as illegal. This combined with an upstream HTTP proxy
+that understands the request payload boundary differently can result in
+"request smuggling" or "desync attacks".