diff --git a/paperless-frontend/src/components/DocumentEditModal.tsx b/paperless-frontend/src/components/DocumentEditModal.tsx
index ea3b728..7943695 100644
--- a/paperless-frontend/src/components/DocumentEditModal.tsx
+++ b/paperless-frontend/src/components/DocumentEditModal.tsx
@@ -9,6 +9,7 @@ import type { Client } from '../api/inbox';
 import { paperlessApi } from '../api/paperless';
 import type { PaperlessDocType, PaperlessCorrespondent } from '../api/paperless';
 import { getEnv } from '../utils/env';
+import { AuthIframe, openAuthUrl } from '../utils/auth-resource';
 import DocumentSearchModal from './DocumentSearchModal';
 
 const { Option } = Select;
@@ -468,7 +469,7 @@ export default function DocumentEditModal({ documentId, document, open, onClose,
                                                         icon={<EyeOutlined />} 
                                                         onClick={(e) => {
                                                             e.stopPropagation();
-                                                            window.open(`${getEnv('VITE_API_URL')}/api/paperless/inbox/pdf/${currentId}`, '_blank');
+                                                            openAuthUrl(`${getEnv('VITE_API_URL')}/api/paperless/inbox/pdf/${currentId}`);
                                                         }}
                                                     />
                                                 )}
@@ -508,9 +509,9 @@ export default function DocumentEditModal({ documentId, document, open, onClose,
                     </Form>
                 </Col>
                 <Col span={14} style={{ height: '100%' }}>
-                    <iframe 
-                      src={`${getEnv('VITE_API_URL')}/api/paperless/inbox/pdf/${documentId}#toolbar=0`} 
-                      style={{ width: '100%', height: '100%', border: 'none' }}
+                    <AuthIframe
+                      src={`${getEnv('VITE_API_URL')}/api/paperless/inbox/pdf/${documentId}#toolbar=0`}
+                      style={{ width: '100%', height: '100%' }}
                       title="PDF Preview"
                     />
                 </Col>
diff --git a/paperless-frontend/src/components/DocumentSearchModal.tsx b/paperless-frontend/src/components/DocumentSearchModal.tsx
index a2cc0ee..3a5573b 100644
--- a/paperless-frontend/src/components/DocumentSearchModal.tsx
+++ b/paperless-frontend/src/components/DocumentSearchModal.tsx
@@ -1,8 +1,9 @@
 import { useState, useCallback, useEffect } from 'react';
-import { Modal, Input, List, Image, Typography, Space, Pagination, Spin, Button } from 'antd';
+import { Modal, Input, List, Typography, Space, Pagination, Spin, Button } from 'antd';
 import { SearchOutlined, CheckOutlined } from '@ant-design/icons';
 import { paperlessApi } from '../api/paperless';
 import { getEnv } from '../utils/env';
+import { AuthImage } from '../utils/auth-resource';
 import dayjs from 'dayjs';
 
 const { Text } = Typography;
@@ -88,12 +89,11 @@ export default function DocumentSearchModal({ open, onCancel, onSelect }: Props)
             >
               <List.Item.Meta
                 avatar={
-                  <Image
+                  <AuthImage
                     src={`${getEnv('VITE_API_URL')}/api/paperless/inbox/preview/${doc.id}`}
                     width={80}
                     height={110}
                     style={{ objectFit: 'cover', borderRadius: 4, border: '1px solid #f0f0f0' }}
-                    preview={false}
                   />
                 }
                 title={doc.title}
diff --git a/paperless-frontend/src/pages/ManuellBearbeitenPage.tsx b/paperless-frontend/src/pages/ManuellBearbeitenPage.tsx
index 7dd9ac5..56bce0a 100644
--- a/paperless-frontend/src/pages/ManuellBearbeitenPage.tsx
+++ b/paperless-frontend/src/pages/ManuellBearbeitenPage.tsx
@@ -1,11 +1,12 @@
 import { useEffect, useState } from 'react';
-import { Table, Popover, Image, Button, Space, message, ConfigProvider, Tooltip } from 'antd';
+import { Table, Popover, Button, Space, message, ConfigProvider, Tooltip } from 'antd';
 import { ReloadOutlined } from '@ant-design/icons';
 import dayjs from 'dayjs';
 import { posteingangApi } from '../api/posteingang';
 import type { PosteingangDocument } from '../api/posteingang';
 import DocumentEditModal from '../components/DocumentEditModal';
 import { getEnv } from '../utils/env';
+import { AuthImage } from '../utils/auth-resource';
 
 export default function ManuellBearbeitenPage() {
   const [data, setData] = useState<PosteingangDocument[]>([]);
@@ -55,10 +56,9 @@ export default function ManuellBearbeitenPage() {
   };
 
   const popoverContent = (id: number) => (
-    <Image 
-       src={`${getEnv('VITE_API_URL')}/api/paperless/inbox/preview/${id}`} 
-       width={400} 
-       preview={false} 
+    <AuthImage
+      src={`${getEnv('VITE_API_URL')}/api/paperless/inbox/preview/${id}`}
+      width={400}
     />
   );
 
@@ -69,10 +69,9 @@ export default function ManuellBearbeitenPage() {
       width: 150,
       render: (_: any, record: PosteingangDocument) => (
         <Popover content={popoverContent(record.id)} placement="right" trigger="hover">
-          <Image 
-            src={`${getEnv('VITE_API_URL')}/api/paperless/inbox/preview/${record.id}`} 
+          <AuthImage
+            src={`${getEnv('VITE_API_URL')}/api/paperless/inbox/preview/${record.id}`}
             width={100}
-            preview={false}
             style={{ border: '1px solid #d9d9d9', objectFit: 'contain' }}
           />
         </Popover>
diff --git a/paperless-frontend/src/pages/PosteingangPage.tsx b/paperless-frontend/src/pages/PosteingangPage.tsx
index 42c8741..b612c1a 100644
--- a/paperless-frontend/src/pages/PosteingangPage.tsx
+++ b/paperless-frontend/src/pages/PosteingangPage.tsx
@@ -1,5 +1,6 @@
 import { useEffect, useState } from 'react';
-import { Table, Popover, Image, Button, Space, message, ConfigProvider, Tooltip } from 'antd';
+import { Table, Popover, Button, Space, message, ConfigProvider, Tooltip } from 'antd';
+import { AuthImage } from '../utils/auth-resource';
 import { ReloadOutlined } from '@ant-design/icons';
 import dayjs from 'dayjs';
 import { posteingangApi } from '../api/posteingang';
@@ -55,10 +56,9 @@ export default function PosteingangPage() {
   };
 
   const popoverContent = (id: number) => (
-    <Image 
-       src={`${getEnv('VITE_API_URL')}/api/paperless/inbox/preview/${id}`} 
-       width={400} 
-       preview={false} 
+    <AuthImage
+      src={`${getEnv('VITE_API_URL')}/api/paperless/inbox/preview/${id}`}
+      width={400}
     />
   );
 
@@ -69,10 +69,9 @@ export default function PosteingangPage() {
       width: 150,
       render: (_: any, record: PosteingangDocument) => (
         <Popover content={popoverContent(record.id)} placement="right" trigger="hover">
-          <Image 
-            src={`${getEnv('VITE_API_URL')}/api/paperless/inbox/preview/${record.id}`} 
+          <AuthImage
+            src={`${getEnv('VITE_API_URL')}/api/paperless/inbox/preview/${record.id}`}
             width={100}
-            preview={false}
             style={{ border: '1px solid #d9d9d9', objectFit: 'contain' }}
           />
         </Popover>
diff --git a/paperless-frontend/src/utils/auth-resource.tsx b/paperless-frontend/src/utils/auth-resource.tsx
new file mode 100644
index 0000000..ac5b3d5
--- /dev/null
+++ b/paperless-frontend/src/utils/auth-resource.tsx
@@ -0,0 +1,107 @@
+import { useState, useEffect } from 'react';
+import { Spin } from 'antd';
+import type { CSSProperties } from 'react';
+import { getAccessToken } from '../auth/oidc';
+
+export function useAuthUrl(url: string | null | undefined): string | null {
+  const [blobUrl, setBlobUrl] = useState<string | null>(null);
+
+  useEffect(() => {
+    if (!url) {
+      setBlobUrl(null);
+      return;
+    }
+    let cancelled = false;
+    let objectUrl: string | undefined;
+
+    (async () => {
+      try {
+        const token = await getAccessToken();
+        if (cancelled) return;
+        const res = await fetch(url, { headers: { Authorization: `Bearer ${token}` } });
+        if (cancelled || !res.ok) return;
+        const blob = await res.blob();
+        if (cancelled) return;
+        objectUrl = URL.createObjectURL(blob);
+        setBlobUrl(objectUrl);
+      } catch {
+        // image/resource just won't show
+      }
+    })();
+
+    return () => {
+      cancelled = true;
+      setBlobUrl(null);
+      if (objectUrl) URL.revokeObjectURL(objectUrl);
+    };
+  }, [url]);
+
+  return blobUrl;
+}
+
+interface AuthImageProps {
+  src: string;
+  width?: number | string;
+  height?: number | string;
+  style?: CSSProperties;
+  alt?: string;
+}
+
+export function AuthImage({ src, width, height, style, alt = '' }: AuthImageProps) {
+  const blobUrl = useAuthUrl(src);
+  if (!blobUrl) {
+    return (
+      <div
+        style={{
+          width,
+          height: height ?? width,
+          display: 'flex',
+          alignItems: 'center',
+          justifyContent: 'center',
+          background: '#f5f5f5',
+          borderRadius: style?.borderRadius ?? 0,
+        }}
+      >
+        <Spin size="small" />
+      </div>
+    );
+  }
+  return <img src={blobUrl} width={width} height={height} style={style} alt={alt} />;
+}
+
+interface AuthIframeProps {
+  src: string;
+  style?: CSSProperties;
+  title?: string;
+}
+
+export function AuthIframe({ src, style, title }: AuthIframeProps) {
+  const hashIdx = src.indexOf('#');
+  const cleanUrl = hashIdx >= 0 ? src.slice(0, hashIdx) : src;
+  const hash = hashIdx >= 0 ? src.slice(hashIdx) : '';
+
+  const blobUrl = useAuthUrl(cleanUrl);
+
+  if (!blobUrl) {
+    return (
+      <div style={{ display: 'flex', alignItems: 'center', justifyContent: 'center', ...style }}>
+        <Spin />
+      </div>
+    );
+  }
+  return <iframe src={`${blobUrl}${hash}`} style={{ border: 'none', ...style }} title={title} />;
+}
+
+export async function openAuthUrl(url: string): Promise<void> {
+  try {
+    const token = await getAccessToken();
+    const res = await fetch(url, { headers: { Authorization: `Bearer ${token}` } });
+    if (!res.ok) return;
+    const blob = await res.blob();
+    const blobUrl = URL.createObjectURL(blob);
+    window.open(blobUrl, '_blank');
+    setTimeout(() => URL.revokeObjectURL(blobUrl), 60_000);
+  } catch {
+    // silently fail
+  }
+}