diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7bb5324a0..b138ff035 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,7 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Migrated the asset profile dialogs of the market data management in the admin control panel to dedicated routes
 
-## 3.67.0 - 2026-09-05
+## 3.67.1 - 2026-09-05
 
 ### Added
 
diff --git a/apps/api/src/app/subscription/subscription.controller.ts b/apps/api/src/app/subscription/subscription.controller.ts
index 0cfc4d90e..778e32243 100644
--- a/apps/api/src/app/subscription/subscription.controller.ts
+++ b/apps/api/src/app/subscription/subscription.controller.ts
@@ -1,4 +1,5 @@
 import { AllowDuringImpersonation } from '@ghostfolio/api/decorators/allow-during-impersonation.decorator';
+import { CustomThrottlerGuard } from '@ghostfolio/api/guards/custom-throttler.guard';
 import { HasPermissionGuard } from '@ghostfolio/api/guards/has-permission.guard';
 import { ConfigurationService } from '@ghostfolio/api/services/configuration/configuration.service';
 import { PropertyService } from '@ghostfolio/api/services/property/property.service';
@@ -46,7 +47,7 @@ export class SubscriptionController {
 
   @Post('redeem-coupon')
   @HttpCode(StatusCodes.OK)
-  @UseGuards(AuthGuard('jwt'), HasPermissionGuard)
+  @UseGuards(AuthGuard('jwt'), CustomThrottlerGuard, HasPermissionGuard)
   public async redeemCoupon(@Body() { couponCode }: { couponCode: string }) {
     if (!this.request.user) {
       throw new HttpException(
@@ -119,7 +120,7 @@ export class SubscriptionController {
   }
 
   @Post('stripe/checkout-session')
-  @UseGuards(AuthGuard('jwt'), HasPermissionGuard)
+  @UseGuards(AuthGuard('jwt'), CustomThrottlerGuard, HasPermissionGuard)
   public async createStripeCheckoutSession(
     @Body() { couponId, priceId }: { couponId?: string; priceId: string }
   ): Promise<CreateStripeCheckoutSessionResponse> {
diff --git a/apps/api/src/app/subscription/subscription.service.ts b/apps/api/src/app/subscription/subscription.service.ts
index aaa4deb5a..312b8c3ae 100644
--- a/apps/api/src/app/subscription/subscription.service.ts
+++ b/apps/api/src/app/subscription/subscription.service.ts
@@ -17,7 +17,7 @@ import {
   UserWithSettings
 } from '@ghostfolio/common/types';
 
-import { Injectable, Logger } from '@nestjs/common';
+import { BadRequestException, Injectable, Logger } from '@nestjs/common';
 import { Prisma, Subscription } from '@prisma/client';
 import { addMilliseconds, isBefore } from 'date-fns';
 import ms, { StringValue } from 'ms';
@@ -64,6 +64,14 @@ export class SubscriptionService {
       }
     );
 
+    if (!subscriptionOffer) {
+      throw new BadRequestException('Invalid priceId');
+    }
+
+    if (couponId && couponId !== subscriptionOffer.couponId) {
+      throw new BadRequestException('Invalid couponId');
+    }
+
     const stripeCheckoutSessionCreateParams: Stripe.Checkout.SessionCreateParams =
       {
         cancel_url: `${this.configurationService.get('ROOT_URL')}/${
@@ -77,9 +85,7 @@ export class SubscriptionService {
           }
         ],
         locale: this.getStripeLocale(user.settings?.settings?.language),
-        metadata: subscriptionOffer
-          ? { subscriptionOffer: JSON.stringify(subscriptionOffer) }
-          : {},
+        metadata: { subscriptionOffer: JSON.stringify(subscriptionOffer) },
         mode: 'payment',
         payment_method_types: ['card'],
         success_url: `${this.configurationService.get(
diff --git a/apps/api/src/interceptors/transform-data-source-in-response/transform-data-source-in-response.interceptor.ts b/apps/api/src/interceptors/transform-data-source-in-response/transform-data-source-in-response.interceptor.ts
index cbe5b4363..31bfb620e 100644
--- a/apps/api/src/interceptors/transform-data-source-in-response/transform-data-source-in-response.interceptor.ts
+++ b/apps/api/src/interceptors/transform-data-source-in-response/transform-data-source-in-response.interceptor.ts
@@ -70,6 +70,8 @@ export class TransformDataSourceInResponseInterceptor<
             }
           }
 
+          data.dataProviderInfo = undefined;
+
           if (Object.keys(valueMap).length === 0) {
             return data;
           }
diff --git a/apps/client/src/app/components/holding-detail-dialog/holding-detail-dialog.html b/apps/client/src/app/components/holding-detail-dialog/holding-detail-dialog.html
index 5b0f1682b..2b378a4d6 100644
--- a/apps/client/src/app/components/holding-detail-dialog/holding-detail-dialog.html
+++ b/apps/client/src/app/components/holding-detail-dialog/holding-detail-dialog.html
@@ -358,7 +358,7 @@
               </form>
             </div>
 
-            @if (dataProviderInfo) {
+            @if (dataProviderInfo?.name) {
               <div class="col-md-12 mb-3 text-center">
                 <hr />
                 <gf-data-provider-credits
diff --git a/libs/ui/src/lib/data-provider-credits/data-provider-credits.component.html b/libs/ui/src/lib/data-provider-credits/data-provider-credits.component.html
index 921433620..fb72e72cd 100644
--- a/libs/ui/src/lib/data-provider-credits/data-provider-credits.component.html
+++ b/libs/ui/src/lib/data-provider-credits/data-provider-credits.component.html
@@ -1,5 +1,5 @@
 <small class="text-muted">
-  <ng-container i18n>Market data provided by</ng-container>&nbsp;
+  <ng-container i18n>Market data provided by</ng-container>{{ ' ' }}
   @for (
     dataProviderInfo of dataProviderInfos;
     track dataProviderInfo;
@@ -7,10 +7,7 @@
   ) {
     <a target="_blank" [href]="dataProviderInfo.url">{{
       dataProviderInfo.name
-    }}</a>
-    @if (!last) {
-      ,&nbsp;
-    }
+    }}</a
+    >{{ last ? '.' : ', ' }}
   }
-  .
 </small>
diff --git a/package-lock.json b/package-lock.json
index 39a02c7ad..2b7b58fd8 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "ghostfolio",
-  "version": "3.67.0",
+  "version": "3.67.1",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "ghostfolio",
-      "version": "3.67.0",
+      "version": "3.67.1",
       "hasInstallScript": true,
       "license": "AGPL-3.0",
       "dependencies": {
diff --git a/package.json b/package.json
index c0439aefb..9ee6a75be 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "ghostfolio",
-  "version": "3.67.0",
+  "version": "3.67.1",
   "homepage": "https://ghostfol.io",
   "license": "AGPL-3.0",
   "repository": "https://github.com/ghostfolio/ghostfolio",