diff --git a/src/lib/sessionCrypto.ts b/src/lib/sessionCrypto.ts
index 83898b9..91baa69 100644
--- a/src/lib/sessionCrypto.ts
+++ b/src/lib/sessionCrypto.ts
@@ -88,7 +88,7 @@ export async function encryptJsonToBlob<T>(data: T): Promise<EncryptedBlob> {
   const ciphertext = await window.crypto.subtle.encrypt(
     {
       name: KEY_ALGORITHM,
-      iv: iv as Uint8Array,
+      iv: new Uint8Array(iv),
     },
     sessionKey,
     plaintext,
@@ -121,10 +121,10 @@ export async function decryptBlobToJson<T>(blob: EncryptedBlob): Promise<T> {
   const decrypted = await window.crypto.subtle.decrypt(
     {
       name: KEY_ALGORITHM,
-      iv: iv,
+      iv: new Uint8Array(iv),
     },
     sessionKey,
-    ciphertext,
+    new Uint8Array(ciphertext),
   );
 
   const jsonString = new TextDecoder().decode(decrypted);