diff --git a/apps/browser/src/autofill/fido2/utils/webauthn-utils.ts b/apps/browser/src/autofill/fido2/utils/webauthn-utils.ts
index 07ffa553b07..795e35e1e80 100644
--- a/apps/browser/src/autofill/fido2/utils/webauthn-utils.ts
+++ b/apps/browser/src/autofill/fido2/utils/webauthn-utils.ts
@@ -27,9 +27,11 @@ export class WebauthnUtils {
         residentKey: keyOptions.authenticatorSelection?.residentKey,
         userVerification: keyOptions.authenticatorSelection?.userVerification,
       },
-      challenge: Fido2Utils.bufferToString(keyOptions.challenge),
+      challenge: Fido2Utils.arrayToString(
+        Fido2Utils.bufferSourceToUint8Array(keyOptions.challenge),
+      ),
       excludeCredentials: keyOptions.excludeCredentials?.map((credential) => ({
-        id: Fido2Utils.bufferToString(credential.id),
+        id: Fido2Utils.arrayToString(Fido2Utils.bufferSourceToUint8Array(credential.id)),
         transports: credential.transports,
         type: credential.type,
       })),
@@ -48,7 +50,7 @@ export class WebauthnUtils {
         name: keyOptions.rp.name,
       },
       user: {
-        id: Fido2Utils.bufferToString(keyOptions.user.id),
+        id: Fido2Utils.arrayToString(Fido2Utils.bufferSourceToUint8Array(keyOptions.user.id)),
         displayName: keyOptions.user.displayName,
         name: keyOptions.user.name,
       },
@@ -60,19 +62,19 @@ export class WebauthnUtils {
   static mapCredentialRegistrationResult(result: CreateCredentialResult): PublicKeyCredential {
     const credential = {
       id: result.credentialId,
-      rawId: Fido2Utils.stringToBuffer(result.credentialId),
+      rawId: Fido2Utils.stringToArray(result.credentialId).buffer,
       type: "public-key",
       authenticatorAttachment: "platform",
       response: {
-        clientDataJSON: Fido2Utils.stringToBuffer(result.clientDataJSON),
-        attestationObject: Fido2Utils.stringToBuffer(result.attestationObject),
+        clientDataJSON: Fido2Utils.stringToArray(result.clientDataJSON).buffer,
+        attestationObject: Fido2Utils.stringToArray(result.attestationObject).buffer,
 
         getAuthenticatorData(): ArrayBuffer {
-          return Fido2Utils.stringToBuffer(result.authData);
+          return Fido2Utils.stringToArray(result.authData).buffer;
         },
 
         getPublicKey(): ArrayBuffer {
-          return Fido2Utils.stringToBuffer(result.publicKey);
+          return Fido2Utils.stringToArray(result.publicKey).buffer;
         },
 
         getPublicKeyAlgorithm(): number {
@@ -110,8 +112,12 @@ export class WebauthnUtils {
 
     return {
       allowedCredentialIds:
-        keyOptions.allowCredentials?.map((c) => Fido2Utils.bufferToString(c.id)) ?? [],
-      challenge: Fido2Utils.bufferToString(keyOptions.challenge),
+        keyOptions.allowCredentials?.map((c) =>
+          Fido2Utils.arrayToString(Fido2Utils.bufferSourceToUint8Array(c.id)),
+        ) ?? [],
+      challenge: Fido2Utils.arrayToString(
+        Fido2Utils.bufferSourceToUint8Array(keyOptions.challenge),
+      ),
       rpId: keyOptions.rpId,
       userVerification: keyOptions.userVerification,
       timeout: keyOptions.timeout,
@@ -123,13 +129,13 @@ export class WebauthnUtils {
   static mapCredentialAssertResult(result: AssertCredentialResult): PublicKeyCredential {
     const credential = {
       id: result.credentialId,
-      rawId: Fido2Utils.stringToBuffer(result.credentialId),
+      rawId: Fido2Utils.stringToArray(result.credentialId).buffer,
       type: "public-key",
       response: {
-        authenticatorData: Fido2Utils.stringToBuffer(result.authenticatorData),
-        clientDataJSON: Fido2Utils.stringToBuffer(result.clientDataJSON),
-        signature: Fido2Utils.stringToBuffer(result.signature),
-        userHandle: Fido2Utils.stringToBuffer(result.userHandle),
+        authenticatorData: Fido2Utils.stringToArray(result.authenticatorData).buffer,
+        clientDataJSON: Fido2Utils.stringToArray(result.clientDataJSON).buffer,
+        signature: Fido2Utils.stringToArray(result.signature).buffer,
+        userHandle: Fido2Utils.stringToArray(result.userHandle).buffer,
       } as AuthenticatorAssertionResponse,
       getClientExtensionResults: () => ({}),
       authenticatorAttachment: "platform",
diff --git a/apps/desktop/src/autofill/modal/credentials/fido2-create.component.ts b/apps/desktop/src/autofill/modal/credentials/fido2-create.component.ts
index d5b4984fae5..87452664729 100644
--- a/apps/desktop/src/autofill/modal/credentials/fido2-create.component.ts
+++ b/apps/desktop/src/autofill/modal/credentials/fido2-create.component.ts
@@ -165,9 +165,7 @@ export class Fido2CreateComponent implements OnInit, OnDestroy {
       return;
     }
 
-    const userHandle = Fido2Utils.bufferToString(
-      new Uint8Array(lastRegistrationRequest.userHandle),
-    );
+    const userHandle = Fido2Utils.arrayToString(new Uint8Array(lastRegistrationRequest.userHandle));
 
     this.ciphers$ = combineLatest([
       this.accountService.activeAccount$.pipe(map((a) => a?.id)),
diff --git a/apps/desktop/src/autofill/services/desktop-autofill.service.ts b/apps/desktop/src/autofill/services/desktop-autofill.service.ts
index 24052a20b3c..b84720bb3c1 100644
--- a/apps/desktop/src/autofill/services/desktop-autofill.service.ts
+++ b/apps/desktop/src/autofill/services/desktop-autofill.service.ts
@@ -380,13 +380,13 @@ export class DesktopAutofillService implements OnDestroy {
     if ("credentialId" in request) {
       allowedCredentials = [
         {
-          id: new Uint8Array(request.credentialId).buffer,
+          id: new Uint8Array(request.credentialId),
           type: "public-key" as const,
         },
       ];
     } else {
       allowedCredentials = request.allowedCredentials.map((credentialId) => ({
-        id: new Uint8Array(credentialId).buffer,
+        id: new Uint8Array(credentialId),
         type: "public-key" as const,
       }));
     }
diff --git a/libs/common/src/platform/abstractions/fido2/fido2-authenticator.service.abstraction.ts b/libs/common/src/platform/abstractions/fido2/fido2-authenticator.service.abstraction.ts
index 427266522e9..a4a75d277b7 100644
--- a/libs/common/src/platform/abstractions/fido2/fido2-authenticator.service.abstraction.ts
+++ b/libs/common/src/platform/abstractions/fido2/fido2-authenticator.service.abstraction.ts
@@ -68,7 +68,7 @@ export class Fido2AuthenticatorError extends Error {
 }
 
 export interface PublicKeyCredentialDescriptor {
-  id: ArrayBuffer;
+  id: Uint8Array<ArrayBuffer>;
   transports?: ("ble" | "hybrid" | "internal" | "nfc" | "usb")[];
   type: "public-key";
 }
@@ -89,7 +89,7 @@ export interface Fido2AuthenticatorMakeCredentialsParams {
   };
   /** The user account’s PublicKeyCredentialUserEntity, containing the user handle given by the Relying Party. */
   userEntity: {
-    id: BufferSource;
+    id: Uint8Array<ArrayBuffer>;
     name?: string;
     displayName?: string;
     icon?: string;
@@ -120,10 +120,10 @@ export interface Fido2AuthenticatorMakeCredentialsParams {
 }
 
 export interface Fido2AuthenticatorMakeCredentialResult {
-  credentialId: BufferSource;
-  attestationObject: BufferSource;
-  authData: BufferSource;
-  publicKey: BufferSource;
+  credentialId: Uint8Array<ArrayBuffer>;
+  attestationObject: Uint8Array<ArrayBuffer>;
+  authData: Uint8Array<ArrayBuffer>;
+  publicKey: Uint8Array<ArrayBuffer>;
   publicKeyAlgorithm: number;
 }
 
@@ -153,9 +153,9 @@ export interface Fido2AuthenticatorGetAssertionParams {
 
 export interface Fido2AuthenticatorGetAssertionResult {
   selectedCredential: {
-    id: ArrayBuffer;
-    userHandle?: ArrayBuffer;
+    id: Uint8Array<ArrayBuffer>;
+    userHandle?: Uint8Array<ArrayBuffer>;
   };
-  authenticatorData: ArrayBuffer;
-  signature: ArrayBuffer;
+  authenticatorData: Uint8Array<ArrayBuffer>;
+  signature: Uint8Array<ArrayBuffer>;
 }
diff --git a/libs/common/src/platform/services/fido2/credential-id-utils.spec.ts b/libs/common/src/platform/services/fido2/credential-id-utils.spec.ts
index 1f2217ccd63..76e068ac01c 100644
--- a/libs/common/src/platform/services/fido2/credential-id-utils.spec.ts
+++ b/libs/common/src/platform/services/fido2/credential-id-utils.spec.ts
@@ -9,7 +9,7 @@ describe("credential-id-utils", () => {
         new Uint8Array([
           0x08, 0xd7, 0x0b, 0x74, 0xe9, 0xf5, 0x45, 0x22, 0xa4, 0x25, 0xe5, 0xdc, 0xd4, 0x01, 0x07,
           0xe7,
-        ]).buffer,
+        ]),
       );
     });
 
@@ -20,7 +20,7 @@ describe("credential-id-utils", () => {
         new Uint8Array([
           0x08, 0xd7, 0x0b, 0x74, 0xe9, 0xf5, 0x45, 0x22, 0xa4, 0x25, 0xe5, 0xdc, 0xd4, 0x01, 0x07,
           0xe7,
-        ]).buffer,
+        ]),
       );
     });
 
diff --git a/libs/common/src/platform/services/fido2/credential-id-utils.ts b/libs/common/src/platform/services/fido2/credential-id-utils.ts
index 08ea33114f5..7bd662cf540 100644
--- a/libs/common/src/platform/services/fido2/credential-id-utils.ts
+++ b/libs/common/src/platform/services/fido2/credential-id-utils.ts
@@ -3,13 +3,13 @@
 import { Fido2Utils } from "./fido2-utils";
 import { guidToRawFormat } from "./guid-utils";
 
-export function parseCredentialId(encodedCredentialId: string): ArrayBuffer {
+export function parseCredentialId(encodedCredentialId: string): Uint8Array<ArrayBuffer> {
   try {
     if (encodedCredentialId.startsWith("b64.")) {
-      return Fido2Utils.stringToBuffer(encodedCredentialId.slice(4));
+      return Fido2Utils.stringToArray(encodedCredentialId.slice(4));
     }
 
-    return guidToRawFormat(encodedCredentialId).buffer;
+    return guidToRawFormat(encodedCredentialId);
   } catch {
     return undefined;
   }
@@ -18,16 +18,16 @@ export function parseCredentialId(encodedCredentialId: string): ArrayBuffer {
 /**
  * Compares two credential IDs for equality.
  */
-export function compareCredentialIds(a: ArrayBuffer, b: ArrayBuffer): boolean {
+export function compareCredentialIds(
+  a: Uint8Array<ArrayBuffer>,
+  b: Uint8Array<ArrayBuffer>,
+): boolean {
   if (a.byteLength !== b.byteLength) {
     return false;
   }
 
-  const viewA = new Uint8Array(a);
-  const viewB = new Uint8Array(b);
-
-  for (let i = 0; i < viewA.length; i++) {
-    if (viewA[i] !== viewB[i]) {
+  for (let i = 0; i < a.length; i++) {
+    if (a[i] !== b[i]) {
       return false;
     }
   }
diff --git a/libs/common/src/platform/services/fido2/fido2-authenticator.service.spec.ts b/libs/common/src/platform/services/fido2/fido2-authenticator.service.spec.ts
index 6223e4274bf..d76bf74f4e9 100644
--- a/libs/common/src/platform/services/fido2/fido2-authenticator.service.spec.ts
+++ b/libs/common/src/platform/services/fido2/fido2-authenticator.service.spec.ts
@@ -246,7 +246,7 @@ describe("FidoAuthenticatorService", () => {
           expect(userInterfaceSession.confirmNewCredential).toHaveBeenCalledWith({
             credentialName: params.rpEntity.name,
             userName: params.userEntity.name,
-            userHandle: Fido2Utils.bufferToString(params.userEntity.id),
+            userHandle: Fido2Utils.arrayToString(params.userEntity.id),
             userVerification,
             rpId: params.rpEntity.id,
           } as NewCredentialParams);
@@ -278,7 +278,7 @@ describe("FidoAuthenticatorService", () => {
                   keyCurve: "P-256",
                   rpId: params.rpEntity.id,
                   rpName: params.rpEntity.name,
-                  userHandle: Fido2Utils.bufferToString(params.userEntity.id),
+                  userHandle: Fido2Utils.arrayToString(params.userEntity.id),
                   userName: params.userEntity.name,
                   counter: 0,
                   userDisplayName: params.userEntity.displayName,
@@ -669,8 +669,8 @@ describe("FidoAuthenticatorService", () => {
       const init = async () => {
         keyPair = await createKeyPair();
         credentialIds = [Utils.newGuid(), Utils.newGuid()];
-        const keyValue = Fido2Utils.bufferToString(
-          await crypto.subtle.exportKey("pkcs8", keyPair.privateKey),
+        const keyValue = Fido2Utils.arrayToString(
+          new Uint8Array(await crypto.subtle.exportKey("pkcs8", keyPair.privateKey)),
         );
         ciphers = credentialIds.map((id) =>
           createCipherView(
@@ -735,7 +735,7 @@ describe("FidoAuthenticatorService", () => {
 
         expect(result.selectedCredential.id).toEqual(parseCredentialId(selectedCredentialId));
         expect(result.selectedCredential.userHandle).toEqual(
-          Fido2Utils.stringToBuffer(fido2Credentials[0].userHandle),
+          Fido2Utils.stringToArray(fido2Credentials[0].userHandle),
         );
         expect(rpIdHash).toEqual(
           new Uint8Array([
@@ -772,7 +772,7 @@ describe("FidoAuthenticatorService", () => {
           const counter = result.authenticatorData.slice(33, 37);
           expect(counter).toEqual(new Uint8Array([0, 0, 0x23, 0x29])); // double check that the counter doesn't change
 
-          const signature = Fido2Utils.bufferToString(result.signature);
+          const signature = Fido2Utils.arrayToString(result.signature);
           if (signatures.has(signature)) {
             throw new Error("Found duplicate signature");
           }
@@ -847,7 +847,7 @@ function createCipherView(
   fido2CredentialView.rpId = fido2Credential.rpId ?? RpId;
   fido2CredentialView.counter = fido2Credential.counter ?? 0;
   fido2CredentialView.userHandle =
-    fido2Credential.userHandle ?? Fido2Utils.bufferToString(randomBytes(16));
+    fido2Credential.userHandle ?? Fido2Utils.arrayToString(randomBytes(16));
   fido2CredentialView.userName = fido2Credential.userName;
   fido2CredentialView.keyAlgorithm = fido2Credential.keyAlgorithm ?? "ECDSA";
   fido2CredentialView.keyCurve = fido2Credential.keyCurve ?? "P-256";
@@ -867,7 +867,7 @@ async function createClientDataHash() {
   const clientData = encoder.encode(
     JSON.stringify({
       type: "webauthn.create",
-      challenge: Fido2Utils.bufferToString(randomBytes(16)),
+      challenge: Fido2Utils.arrayToString(randomBytes(16)),
       origin: RpId,
       crossOrigin: false,
     }),
diff --git a/libs/common/src/platform/services/fido2/fido2-authenticator.service.ts b/libs/common/src/platform/services/fido2/fido2-authenticator.service.ts
index 1b150207290..9207e0ac95c 100644
--- a/libs/common/src/platform/services/fido2/fido2-authenticator.service.ts
+++ b/libs/common/src/platform/services/fido2/fido2-authenticator.service.ts
@@ -127,11 +127,11 @@ export class Fido2AuthenticatorService<
       let keyPair: CryptoKeyPair;
       let userVerified = false;
       let credentialId: string;
-      let pubKeyDer: ArrayBuffer;
+      let pubKeyDer: Uint8Array<ArrayBuffer>;
       const response = await userInterfaceSession.confirmNewCredential({
         credentialName: params.rpEntity.name,
         userName: params.userEntity.name,
-        userHandle: Fido2Utils.bufferToString(params.userEntity.id),
+        userHandle: Fido2Utils.arrayToString(params.userEntity.id),
         userVerification: params.requireUserVerification,
         rpId: params.rpEntity.id,
       });
@@ -147,7 +147,7 @@ export class Fido2AuthenticatorService<
 
       try {
         keyPair = await createKeyPair();
-        pubKeyDer = await crypto.subtle.exportKey("spki", keyPair.publicKey);
+        pubKeyDer = new Uint8Array(await crypto.subtle.exportKey("spki", keyPair.publicKey));
         const activeUserId = await firstValueFrom(
           this.accountService.activeAccount$.pipe(getUserId),
         );
@@ -349,7 +349,7 @@ export class Fido2AuthenticatorService<
           authenticatorData,
           selectedCredential: {
             id: parseCredentialId(selectedCredentialId),
-            userHandle: Fido2Utils.stringToBuffer(selectedFido2Credential.userHandle),
+            userHandle: Fido2Utils.stringToArray(selectedFido2Credential.userHandle),
           },
           signature,
         };
@@ -487,15 +487,15 @@ async function createKeyView(
     throw new Fido2AuthenticatorError(Fido2AuthenticatorErrorCode.Unknown);
   }
 
-  const pkcs8Key = await crypto.subtle.exportKey("pkcs8", keyValue);
+  const pkcs8Key = new Uint8Array(await crypto.subtle.exportKey("pkcs8", keyValue));
   const fido2Credential = new Fido2CredentialView();
   fido2Credential.credentialId = Utils.newGuid();
   fido2Credential.keyType = "public-key";
   fido2Credential.keyAlgorithm = "ECDSA";
   fido2Credential.keyCurve = "P-256";
-  fido2Credential.keyValue = Fido2Utils.bufferToString(pkcs8Key);
+  fido2Credential.keyValue = Fido2Utils.arrayToString(pkcs8Key);
   fido2Credential.rpId = params.rpEntity.id;
-  fido2Credential.userHandle = Fido2Utils.bufferToString(params.userEntity.id);
+  fido2Credential.userHandle = Fido2Utils.arrayToString(params.userEntity.id);
   fido2Credential.userName = params.userEntity.name;
   fido2Credential.counter = 0;
   fido2Credential.rpName = params.rpEntity.name;
@@ -509,7 +509,7 @@ async function createKeyView(
 async function getPrivateKeyFromFido2Credential(
   fido2Credential: Fido2CredentialView,
 ): Promise<CryptoKey> {
-  const keyBuffer = Fido2Utils.stringToBuffer(fido2Credential.keyValue);
+  const keyBuffer = Fido2Utils.stringToArray(fido2Credential.keyValue);
   return await crypto.subtle.importKey(
     "pkcs8",
     new Uint8Array(keyBuffer),
@@ -535,7 +535,10 @@ async function generateAuthData(params: AuthDataParams) {
   const authData: Array<number> = [];
 
   const rpIdHash = new Uint8Array(
-    await crypto.subtle.digest({ name: "SHA-256" }, Utils.fromByteStringToArray(params.rpId)),
+    await crypto.subtle.digest(
+      { name: "SHA-256" },
+      Utils.fromByteStringToArray(params.rpId) as BufferSource,
+    ),
   );
   authData.push(...rpIdHash);
 
diff --git a/libs/common/src/platform/services/fido2/fido2-client.service.spec.ts b/libs/common/src/platform/services/fido2/fido2-client.service.spec.ts
index 7b298110040..08f8abb1549 100644
--- a/libs/common/src/platform/services/fido2/fido2-client.service.spec.ts
+++ b/libs/common/src/platform/services/fido2/fido2-client.service.spec.ts
@@ -572,9 +572,9 @@ describe("FidoAuthenticatorService", () => {
     describe("assert non-discoverable credential", () => {
       it("should call authenticator.assertCredential", async () => {
         const allowedCredentialIds = [
-          Fido2Utils.bufferToString(guidToRawFormat(Utils.newGuid())),
-          Fido2Utils.bufferToString(guidToRawFormat(Utils.newGuid())),
-          Fido2Utils.bufferToString(Utils.fromByteStringToArray("not-a-guid")),
+          Fido2Utils.arrayToString(guidToRawFormat(Utils.newGuid())),
+          Fido2Utils.arrayToString(guidToRawFormat(Utils.newGuid())),
+          Fido2Utils.arrayToString(Utils.fromByteStringToArray("not-a-guid")),
         ];
         const params = createParams({
           userVerification: "required",
@@ -590,13 +590,13 @@ describe("FidoAuthenticatorService", () => {
             rpId: RpId,
             allowCredentialDescriptorList: [
               expect.objectContaining({
-                id: Fido2Utils.stringToBuffer(allowedCredentialIds[0]),
+                id: Fido2Utils.stringToArray(allowedCredentialIds[0]),
               }),
               expect.objectContaining({
-                id: Fido2Utils.stringToBuffer(allowedCredentialIds[1]),
+                id: Fido2Utils.stringToArray(allowedCredentialIds[1]),
               }),
               expect.objectContaining({
-                id: Fido2Utils.stringToBuffer(allowedCredentialIds[2]),
+                id: Fido2Utils.stringToArray(allowedCredentialIds[2]),
               }),
             ],
           }),
@@ -688,7 +688,7 @@ describe("FidoAuthenticatorService", () => {
     function createParams(params: Partial<AssertCredentialParams> = {}): AssertCredentialParams {
       return {
         allowedCredentialIds: params.allowedCredentialIds ?? [],
-        challenge: params.challenge ?? Fido2Utils.bufferToString(randomBytes(16)),
+        challenge: params.challenge ?? Fido2Utils.arrayToString(randomBytes(16)),
         origin: params.origin ?? Origin,
         rpId: params.rpId ?? RpId,
         timeout: params.timeout,
diff --git a/libs/common/src/platform/services/fido2/fido2-client.service.ts b/libs/common/src/platform/services/fido2/fido2-client.service.ts
index 8fabed450f8..b80023b8bc2 100644
--- a/libs/common/src/platform/services/fido2/fido2-client.service.ts
+++ b/libs/common/src/platform/services/fido2/fido2-client.service.ts
@@ -130,7 +130,7 @@ export class Fido2ClientService<
       throw new DOMException("Invalid 'sameOriginWithAncestors' value", "NotAllowedError");
     }
 
-    const userId = Fido2Utils.stringToBuffer(params.user.id);
+    const userId = Fido2Utils.stringToArray(params.user.id);
     if (userId.byteLength < 1 || userId.byteLength > 64) {
       this.logService?.warning(
         `[Fido2Client] Invalid 'user.id' length: ${params.user.id} (${userId.byteLength})`,
@@ -195,7 +195,7 @@ export class Fido2ClientService<
     const makeCredentialParams = mapToMakeCredentialParams({
       params,
       credTypesAndPubKeyAlgs,
-      clientDataHash,
+      clientDataHash: new Uint8Array(clientDataHash),
     });
 
     // Set timeout before invoking authenticator
@@ -255,11 +255,11 @@ export class Fido2ClientService<
     timeoutSubscription?.unsubscribe();
 
     return {
-      credentialId: Fido2Utils.bufferToString(makeCredentialResult.credentialId),
-      attestationObject: Fido2Utils.bufferToString(makeCredentialResult.attestationObject),
-      authData: Fido2Utils.bufferToString(makeCredentialResult.authData),
-      clientDataJSON: Fido2Utils.bufferToString(clientDataJSONBytes),
-      publicKey: Fido2Utils.bufferToString(makeCredentialResult.publicKey),
+      credentialId: Fido2Utils.arrayToString(makeCredentialResult.credentialId),
+      attestationObject: Fido2Utils.arrayToString(makeCredentialResult.attestationObject),
+      authData: Fido2Utils.arrayToString(makeCredentialResult.authData),
+      clientDataJSON: Fido2Utils.arrayToString(clientDataJSONBytes),
+      publicKey: Fido2Utils.arrayToString(makeCredentialResult.publicKey),
       publicKeyAlgorithm: makeCredentialResult.publicKeyAlgorithm,
       transports: ["internal", "hybrid"],
       extensions: { credProps },
@@ -383,7 +383,7 @@ export class Fido2ClientService<
     params: AssertCredentialParams,
     tab: ParentWindowReference,
     abortController: AbortController,
-    clientDataJSONBytes: Uint8Array,
+    clientDataJSONBytes: Uint8Array<ArrayBuffer>,
   ): Promise<AssertCredentialResult> {
     let getAssertionResult;
     let assumeUserPresence = false;
@@ -414,7 +414,7 @@ export class Fido2ClientService<
       }
 
       params.allowedCredentialIds = [
-        Fido2Utils.bufferToString(guidToRawFormat(requestResult.credentialId)),
+        Fido2Utils.arrayToString(guidToRawFormat(requestResult.credentialId)),
       ];
       assumeUserPresence = true;
 
@@ -441,17 +441,17 @@ export class Fido2ClientService<
 
   private generateAssertCredentialResult(
     getAssertionResult: Fido2AuthenticatorGetAssertionResult,
-    clientDataJSONBytes: Uint8Array,
+    clientDataJSONBytes: Uint8Array<ArrayBuffer>,
   ): AssertCredentialResult {
     return {
-      authenticatorData: Fido2Utils.bufferToString(getAssertionResult.authenticatorData),
-      clientDataJSON: Fido2Utils.bufferToString(clientDataJSONBytes),
-      credentialId: Fido2Utils.bufferToString(getAssertionResult.selectedCredential.id),
+      authenticatorData: Fido2Utils.arrayToString(getAssertionResult.authenticatorData),
+      clientDataJSON: Fido2Utils.arrayToString(clientDataJSONBytes),
+      credentialId: Fido2Utils.arrayToString(getAssertionResult.selectedCredential.id),
       userHandle:
         getAssertionResult.selectedCredential.userHandle !== undefined
-          ? Fido2Utils.bufferToString(getAssertionResult.selectedCredential.userHandle)
+          ? Fido2Utils.arrayToString(getAssertionResult.selectedCredential.userHandle)
           : undefined,
-      signature: Fido2Utils.bufferToString(getAssertionResult.signature),
+      signature: Fido2Utils.arrayToString(getAssertionResult.signature),
     };
   }
 
@@ -489,11 +489,11 @@ function mapToMakeCredentialParams({
 }: {
   params: CreateCredentialParams;
   credTypesAndPubKeyAlgs: PublicKeyCredentialParam[];
-  clientDataHash: ArrayBuffer;
+  clientDataHash: Uint8Array<ArrayBuffer>;
 }): Fido2AuthenticatorMakeCredentialsParams {
   const excludeCredentialDescriptorList: PublicKeyCredentialDescriptor[] =
     params.excludeCredentials?.map((credential) => ({
-      id: Fido2Utils.stringToBuffer(credential.id),
+      id: Fido2Utils.stringToArray(credential.id),
       transports: credential.transports,
       type: credential.type,
     })) ?? [];
@@ -525,7 +525,7 @@ function mapToMakeCredentialParams({
       name: params.rp.name,
     },
     userEntity: {
-      id: Fido2Utils.stringToBuffer(params.user.id),
+      id: Fido2Utils.stringToArray(params.user.id),
       displayName: params.user.displayName,
       name: params.user.name,
     },
@@ -547,7 +547,7 @@ function mapToGetAssertionParams({
 }): Fido2AuthenticatorGetAssertionParams {
   const allowCredentialDescriptorList: PublicKeyCredentialDescriptor[] =
     params.allowedCredentialIds.map((id) => ({
-      id: Fido2Utils.stringToBuffer(id),
+      id: Fido2Utils.stringToArray(id),
       type: "public-key",
     }));
 
diff --git a/libs/common/src/platform/services/fido2/fido2-utils.ts b/libs/common/src/platform/services/fido2/fido2-utils.ts
index 8efd4734d81..91a772a2b5f 100644
--- a/libs/common/src/platform/services/fido2/fido2-utils.ts
+++ b/libs/common/src/platform/services/fido2/fido2-utils.ts
@@ -42,18 +42,18 @@ export class Fido2Utils {
     };
   }
 
-  static bufferToString(bufferSource: BufferSource): string {
-    return Fido2Utils.fromBufferToB64(Fido2Utils.bufferSourceToUint8Array(bufferSource))
+  static arrayToString(array: Uint8Array<ArrayBuffer>): string {
+    return Fido2Utils.fromBufferToB64(Fido2Utils.bufferSourceToUint8Array(array))
       .replace(/\+/g, "-")
       .replace(/\//g, "_")
       .replace(/=/g, "");
   }
 
-  static stringToBuffer(str: string): ArrayBuffer {
-    return Fido2Utils.fromB64ToArray(Fido2Utils.fromUrlB64ToB64(str)).buffer;
+  static stringToArray(str: string): Uint8Array<ArrayBuffer> {
+    return Fido2Utils.fromB64ToArray(Fido2Utils.fromUrlB64ToB64(str));
   }
 
-  static bufferSourceToUint8Array(bufferSource: BufferSource): Uint8Array {
+  static bufferSourceToUint8Array(bufferSource: BufferSource): Uint8Array<ArrayBuffer> {
     if (Fido2Utils.isArrayBuffer(bufferSource)) {
       return new Uint8Array(bufferSource);
     } else {
@@ -70,7 +70,7 @@ export class Fido2Utils {
     return b64Str.replace(/\+/g, "-").replace(/\//g, "_").replace(/=/g, "");
   }
 
-  static fromBufferToB64(buffer: ArrayBuffer): string {
+  static fromBufferToB64(buffer: Uint8Array | ArrayBuffer): string {
     if (buffer == null) {
       return null;
     }
@@ -83,7 +83,7 @@ export class Fido2Utils {
     return globalThis.btoa(binary);
   }
 
-  static fromB64ToArray(str: string): Uint8Array {
+  static fromB64ToArray(str: string): Uint8Array<ArrayBuffer> {
     if (str == null) {
       return null;
     }
diff --git a/libs/common/src/platform/services/file-upload/azure-file-upload.service.ts b/libs/common/src/platform/services/file-upload/azure-file-upload.service.ts
index 02adcfee22e..8f7626b3c06 100644
--- a/libs/common/src/platform/services/file-upload/azure-file-upload.service.ts
+++ b/libs/common/src/platform/services/file-upload/azure-file-upload.service.ts
@@ -31,7 +31,7 @@ export class AzureFileUploadService {
     });
 
     const request = new Request(url, {
-      body: data.buffer,
+      body: data.buffer as BodyInit,
       cache: "no-store",
       method: "PUT",
       headers: headers,
diff --git a/libs/common/src/platform/services/file-upload/bitwarden-file-upload.service.ts b/libs/common/src/platform/services/file-upload/bitwarden-file-upload.service.ts
index 93594405302..b129f1d5eeb 100644
--- a/libs/common/src/platform/services/file-upload/bitwarden-file-upload.service.ts
+++ b/libs/common/src/platform/services/file-upload/bitwarden-file-upload.service.ts
@@ -10,7 +10,9 @@ export class BitwardenFileUploadService {
     const fd = new FormData();
 
     if (Utils.isBrowser) {
-      const blob = new Blob([encryptedFileData.buffer], { type: "application/octet-stream" });
+      const blob = new Blob([encryptedFileData.buffer as BlobPart], {
+        type: "application/octet-stream",
+      });
       fd.append("data", blob, encryptedFileName);
     } else if (Utils.isNode) {
       fd.append(
diff --git a/libs/key-management-ui/src/lock/services/default-webauthn-prf-unlock.service.ts b/libs/key-management-ui/src/lock/services/default-webauthn-prf-unlock.service.ts
index b3bbf392d0a..ae3d4584d6e 100644
--- a/libs/key-management-ui/src/lock/services/default-webauthn-prf-unlock.service.ts
+++ b/libs/key-management-ui/src/lock/services/default-webauthn-prf-unlock.service.ts
@@ -154,7 +154,7 @@ export class DefaultWebAuthnPrfUnlockService implements WebAuthnPrfUnlockService
         allowCredentials: credentials.map(({ credentialId, transports }) => {
           // The credential ID is already base64url encoded from login storage
           // We need to decode it to ArrayBuffer for WebAuthn
-          const decodedId = Fido2Utils.stringToBuffer(credentialId);
+          const decodedId = Fido2Utils.stringToArray(credentialId);
           return {
             type: "public-key",
             id: decodedId,