diff --git a/libs/auth/src/angular/login-via-auth-request/login-via-auth-request.component.ts b/libs/auth/src/angular/login-via-auth-request/login-via-auth-request.component.ts
index 040d4d3c121..fc91f220138 100644
--- a/libs/auth/src/angular/login-via-auth-request/login-via-auth-request.component.ts
+++ b/libs/auth/src/angular/login-via-auth-request/login-via-auth-request.component.ts
@@ -676,7 +676,7 @@ export class LoginViaAuthRequestComponent implements OnInit, OnDestroy {
 
   private async decryptViaApprovedAuthRequest(
     authRequestResponse: AuthRequestResponse,
-    privateKey: ArrayBuffer,
+    privateKey: Uint8Array,
     userId: UserId,
   ): Promise<void> {
     /**
diff --git a/libs/auth/src/common/abstractions/auth-request.service.abstraction.ts b/libs/auth/src/common/abstractions/auth-request.service.abstraction.ts
index 1bfbfd8d004..1077bc024e9 100644
--- a/libs/auth/src/common/abstractions/auth-request.service.abstraction.ts
+++ b/libs/auth/src/common/abstractions/auth-request.service.abstraction.ts
@@ -72,7 +72,7 @@ export abstract class AuthRequestServiceAbstraction {
    */
   abstract setUserKeyAfterDecryptingSharedUserKey(
     authReqResponse: AuthRequestResponse,
-    authReqPrivateKey: ArrayBuffer,
+    authReqPrivateKey: Uint8Array,
     userId: UserId,
   ): Promise<void>;
   /**
@@ -83,7 +83,7 @@ export abstract class AuthRequestServiceAbstraction {
    */
   abstract setKeysAfterDecryptingSharedMasterKeyAndHash(
     authReqResponse: AuthRequestResponse,
-    authReqPrivateKey: ArrayBuffer,
+    authReqPrivateKey: Uint8Array,
     userId: UserId,
   ): Promise<void>;
   /**
@@ -94,7 +94,7 @@ export abstract class AuthRequestServiceAbstraction {
    */
   abstract decryptPubKeyEncryptedUserKey(
     pubKeyEncryptedUserKey: string,
-    privateKey: ArrayBuffer,
+    privateKey: Uint8Array,
   ): Promise<UserKey>;
   /**
    * Decrypts a `MasterKey` and `MasterKeyHash` from a public key encrypted `MasterKey` and `MasterKeyHash`.
@@ -106,7 +106,7 @@ export abstract class AuthRequestServiceAbstraction {
   abstract decryptPubKeyEncryptedMasterKeyAndHash(
     pubKeyEncryptedMasterKey: string,
     pubKeyEncryptedMasterKeyHash: string,
-    privateKey: ArrayBuffer,
+    privateKey: Uint8Array,
   ): Promise<{ masterKey: MasterKey; masterKeyHash: string }>;
 
   /**
diff --git a/libs/auth/src/common/services/auth-request/auth-request.service.ts b/libs/auth/src/common/services/auth-request/auth-request.service.ts
index ba4b9eaf174..89aad0cdbd7 100644
--- a/libs/auth/src/common/services/auth-request/auth-request.service.ts
+++ b/libs/auth/src/common/services/auth-request/auth-request.service.ts
@@ -213,7 +213,9 @@ export class AuthRequestService implements AuthRequestServiceAbstraction {
     );
 
     const masterKey = new SymmetricCryptoKey(decryptedMasterKeyArrayBuffer) as MasterKey;
-    const masterKeyHash = Utils.fromBufferToUtf8(decryptedMasterKeyHashArrayBuffer);
+    const masterKeyHash = Utils.fromBufferToUtf8(
+      decryptedMasterKeyHashArrayBuffer.buffer as ArrayBuffer,
+    );
 
     return {
       masterKey,
diff --git a/libs/common/src/auth/models/domain/admin-auth-req-storable.ts b/libs/common/src/auth/models/domain/admin-auth-req-storable.ts
index bdb74ebbc6b..34f1d367ffc 100644
--- a/libs/common/src/auth/models/domain/admin-auth-req-storable.ts
+++ b/libs/common/src/auth/models/domain/admin-auth-req-storable.ts
@@ -17,7 +17,7 @@ export class AdminAuthRequestStorable {
   toJSON() {
     return {
       id: this.id,
-      privateKey: Utils.fromBufferToByteString(this.privateKey),
+      privateKey: Utils.fromBufferToByteString(this.privateKey.buffer as ArrayBuffer),
     };
   }
 
diff --git a/libs/common/src/auth/models/response/two-factor-web-authn.response.ts b/libs/common/src/auth/models/response/two-factor-web-authn.response.ts
index 35b6830b0df..d8de2e1247e 100644
--- a/libs/common/src/auth/models/response/two-factor-web-authn.response.ts
+++ b/libs/common/src/auth/models/response/two-factor-web-authn.response.ts
@@ -41,7 +41,8 @@ export class ChallengeResponse extends BaseResponse implements PublicKeyCredenti
     super(response);
     this.attestation = this.getResponseProperty("attestation");
     this.authenticatorSelection = this.getResponseProperty("authenticatorSelection");
-    this.challenge = Utils.fromUrlB64ToArray(this.getResponseProperty("challenge"));
+    this.challenge = Utils.fromUrlB64ToArray(this.getResponseProperty("challenge"))
+      .buffer as ArrayBuffer;
     this.excludeCredentials = this.getResponseProperty("excludeCredentials").map((c: any) => {
       c.id = Utils.fromUrlB64ToArray(c.id).buffer;
       return c;