diff --git a/crates/openssl-src/RUSTSEC-0000-0000.md b/crates/openssl-src/RUSTSEC-0000-0000.md
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+```toml
+[advisory]
+id = "RUSTSEC-0000-0000"
+package = "openssl-src"
+aliases = ["CVE-2021-23840"]
+categories = ["denial-of-service"]
+date = "2021-05-01"
+url = "https://www.openssl.org/news/secadv/20210216.txt"
+
+[versions]
+patched = [">= 111.14"]
+```
+
+# Integer overflow in CipherUpdate
+
+Calls to `EVP_CipherUpdate`, `EVP_EncryptUpdate` and `EVP_DecryptUpdate` may overflow
+the output length argument in some cases where the input length is close to the
+maximum permissable length for an integer on the platform. In such cases the
+return value from the function call will be 1 (indicating success), but the
+output length value will be negative. This could cause applications to behave
+incorrectly or crash.
+