diff --git a/postgres-protocol/Cargo.toml b/postgres-protocol/Cargo.toml
index a4ed3e90..638778f2 100644
--- a/postgres-protocol/Cargo.toml
+++ b/postgres-protocol/Cargo.toml
@@ -13,9 +13,9 @@ base64 = "0.13"
 byteorder = "1.0"
 bytes = "1.0"
 fallible-iterator = "0.2"
-hmac = "0.11"
-md-5 = "0.9"
+hmac = "0.12"
+md-5 = "0.10"
 memchr = "2.0"
 rand = "0.8"
-sha2 = "0.9"
+sha2 = "0.10"
 stringprep = "0.1"
diff --git a/postgres-protocol/src/authentication/sasl.rs b/postgres-protocol/src/authentication/sasl.rs
index a3704ce1..ea2f55ca 100644
--- a/postgres-protocol/src/authentication/sasl.rs
+++ b/postgres-protocol/src/authentication/sasl.rs
@@ -1,6 +1,6 @@
 //! SASL-based authentication support.
 
-use hmac::{Hmac, Mac, NewMac};
+use hmac::{Hmac, Mac};
 use rand::{self, Rng};
 use sha2::digest::FixedOutput;
 use sha2::{Digest, Sha256};
@@ -275,7 +275,7 @@ impl ScramSha256 {
         let mut hmac = Hmac::<Sha256>::new_from_slice(&server_key)
             .expect("HMAC is able to accept all key sizes");
         hmac.update(auth_message.as_bytes());
-        hmac.verify(&verifier)
+        hmac.verify_slice(&verifier)
             .map_err(|_| io::Error::new(io::ErrorKind::InvalidInput, "SCRAM verification error"))
     }
 }
diff --git a/postgres-protocol/src/password/mod.rs b/postgres-protocol/src/password/mod.rs
index 1b32ae8f..a60687bb 100644
--- a/postgres-protocol/src/password/mod.rs
+++ b/postgres-protocol/src/password/mod.rs
@@ -7,7 +7,7 @@
 //! end up in logs pg_stat displays, etc.
 
 use crate::authentication::sasl;
-use hmac::{Hmac, Mac, NewMac};
+use hmac::{Hmac, Mac};
 use md5::Md5;
 use rand::RngCore;
 use sha2::digest::FixedOutput;