diff --git a/vault-api/Cargo.toml b/vault-api/Cargo.toml
index c73cdfb..877a9b6 100644
--- a/vault-api/Cargo.toml
+++ b/vault-api/Cargo.toml
@@ -17,7 +17,7 @@ chrono = { version = "0.4", features = ["serde"] }
 futures = "0.1"
 hyper = {version = "0.10", optional = true}
 hyper-openssl = {version = "0.2", optional = true }
-iron = {version = "0.5", optional = true}
+iron = {version = "0.6", optional = true}
 swagger = "0.7"
 
 # Not required by example server.