diff --git a/packages/server/src/authenticatorKey/parseFidoPackedKey.js b/packages/server/src/authenticatorKey/parseFidoPackedKey.js
index 8dfa526..dd2bba8 100644
--- a/packages/server/src/authenticatorKey/parseFidoPackedKey.js
+++ b/packages/server/src/authenticatorKey/parseFidoPackedKey.js
@@ -129,7 +129,7 @@ exports.validateFidoPackedKey = (
     }
 
     const clientDataHash = hash(
-        'SHA256',
+        'sha256',
         Buffer.from(clientDataJSON, 'base64')
     );
     const signatureBaseBuffer = Buffer.concat([
diff --git a/packages/server/src/authenticatorKey/parseFidoU2FKey.js b/packages/server/src/authenticatorKey/parseFidoU2FKey.js
index 876b038..bebbe08 100644
--- a/packages/server/src/authenticatorKey/parseFidoU2FKey.js
+++ b/packages/server/src/authenticatorKey/parseFidoU2FKey.js
@@ -14,7 +14,7 @@ exports.parseFidoU2FKey = (authenticatorKey, clientDataJSON) => {
     }
 
     const clientDataHash = hash(
-        'SHA256',
+        'sha256',
         Buffer.from(clientDataJSON, 'base64')
     );
     const reservedByte = Buffer.from([0x00]);
@@ -59,7 +59,7 @@ exports.validateFidoU2FKey = (
     }
 
     const clientDataHash = hash(
-        'SHA256',
+        'sha256',
         Buffer.from(clientDataJSON, 'base64')
     );
     const signatureBase = Buffer.concat([
diff --git a/packages/server/src/utils.js b/packages/server/src/utils.js
index 5cd831d..af6f7ea 100644
--- a/packages/server/src/utils.js
+++ b/packages/server/src/utils.js
@@ -101,7 +101,7 @@ exports.verifySignature = (
     data,
     publicKey
 ) => {
-    return createVerify('SHA256')
+    return createVerify('sha256')
         .update(data)
         .verify(publicKey, signature);
 };