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+```toml
+[advisory]
+id = "RUSTSEC-0000-0000"
+package = "tungstenite"
+date = "2023-09-25"
+url = "https://github.com/snapview/tungstenite-rs/issues/376"
+categories = ["denial-of-service"]
+aliases = ["CVE-2023-43669", "GHSA-9mcr-873m-xcxp"]
+cvss = "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
+
+[versions]
+patched = [">= 0.20.1"]
+```
+
+# Tungstenite allows remote attackers to cause a denial of service
+
+The Tungstenite crate through 0.20.0 for Rust allows remote attackers to cause
+a denial of service (minutes of CPU consumption) via an excessive length of an
+HTTP header in a client handshake. The length affects both how many times a parse
+is attempted (e.g., thousands of times) and the average amount of data for each
+parse attempt (e.g., millions of bytes).