diff --git a/Cargo.toml b/Cargo.toml
index 6202b60d..08a76e80 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -23,7 +23,7 @@ read_buf = ["rustls/read_buf"]
 
 [dependencies]
 # Keep in sync with RUSTLS_CRATE_VERSION in build.rs
-rustls = { version = "=0.21.0", features = [ "dangerous_configuration" ] }
+rustls = { version = "=0.21.5", features = [ "dangerous_configuration" ] }
 webpki = "0.22"
 libc = "0.2"
 sct = "0.7"