diff --git a/web/src/components/document-preview/hooks.ts b/web/src/components/document-preview/hooks.ts
index b6bcf67761..921b83ed13 100644
--- a/web/src/components/document-preview/hooks.ts
+++ b/web/src/components/document-preview/hooks.ts
@@ -129,10 +129,10 @@ export const useFetchExcel = (filePath: string) => {
     myExcelPreviewer
       ?.preview(jsonFile.data)
       .then(() => {
-        console.log('succeed');
         setStatus(true);
       })
       .catch((e) => {
+        // eslint-disable-next-line no-console
         console.warn('failed', e);
         myExcelPreviewer.destroy();
         setStatus(false);
@@ -155,9 +155,19 @@ export const useCatchDocumentError = (url: string) => {
   const [error, setError] = useState<string>('');
 
   const fetchDocument = useCallback(async () => {
-    const { data } = await axios.get(url, { headers: httpHeaders });
-    if (data.code !== 0) {
-      setError(data?.message);
+    try {
+      const { data } = await axios.get(url, { headers: httpHeaders });
+      // Only treat as error if response is JSON with an error code
+      // Binary data (like PDF) won't have a code property
+      if (data && typeof data === 'object' && 'code' in data && data.code !== 0) {
+        setError(data?.message || 'Failed to load document');
+      }
+    } catch (e) {
+      // Network errors or non-2xx responses
+      const errMsg = e instanceof Error ? e.message : 'Failed to load document';
+      if (errMsg) {
+        setError(errMsg);
+      }
     }
   }, [url, httpHeaders]);
   useEffect(() => {
diff --git a/web/src/components/document-preview/index.tsx b/web/src/components/document-preview/index.tsx
index dc764ce6f1..e94d2e7347 100644
--- a/web/src/components/document-preview/index.tsx
+++ b/web/src/components/document-preview/index.tsx
@@ -23,9 +23,11 @@ const DocumentPreview = function ({
   setWidthAndHeight,
   url,
 }: PreviewProps & Partial<IProps>) {
+  const isPdf = fileType === 'pdf';
+
   return (
     <>
-      {fileType === 'pdf' && highlights && setWidthAndHeight && (
+      {isPdf && (
         <section className="h-full">
           <PdfPreviewer
             className={className}
diff --git a/web/src/components/file-icon/index.tsx b/web/src/components/file-icon/index.tsx
index e2f549fe76..42da7d3ed6 100644
--- a/web/src/components/file-icon/index.tsx
+++ b/web/src/components/file-icon/index.tsx
@@ -2,6 +2,7 @@ import { getExtension } from '@/utils/document-util';
 import SvgIcon from '../svg-icon';
 
 import { useFetchDocumentThumbnailsByIds } from '@/hooks/use-document-request';
+import { useAuthenticatedImageUrl } from '@/components/image';
 import { useEffect } from 'react';
 import styles from './index.module.less';
 
@@ -16,6 +17,7 @@ const FileIcon = ({ name, id }: IProps) => {
   const { data: fileThumbnails, setDocumentIds } =
     useFetchDocumentThumbnailsByIds();
   const fileThumbnail = fileThumbnails[id];
+  const blobUrl = useAuthenticatedImageUrl(fileThumbnail);
 
   useEffect(() => {
     if (id) {
@@ -23,8 +25,8 @@ const FileIcon = ({ name, id }: IProps) => {
     }
   }, [id, setDocumentIds]);
 
-  return fileThumbnail ? (
-    <img src={fileThumbnail} className={styles.thumbnailImg}></img>
+  return blobUrl ? (
+    <img src={blobUrl} className={styles.thumbnailImg}></img>
   ) : (
     <SvgIcon name={`file-icon/${fileExtension}`} width={24}></SvgIcon>
   );
diff --git a/web/src/components/floating-chat-widget-markdown.tsx b/web/src/components/floating-chat-widget-markdown.tsx
index 88f5ed7ce1..4bd9e5cbb0 100644
--- a/web/src/components/floating-chat-widget-markdown.tsx
+++ b/web/src/components/floating-chat-widget-markdown.tsx
@@ -1,4 +1,4 @@
-import Image from '@/components/image';
+import Image, { AuthenticatedImg } from '@/components/image';
 import SvgIcon from '@/components/svg-icon';
 
 import { MarkdownRemarkPlugins } from '@/constants/markdown-remark-plugins';
@@ -197,7 +197,7 @@ const FloatingChatWidgetMarkdown = ({
             {documentId && (
               <section className="flex gap-1 justify-center">
                 {fileThumbnail ? (
-                  <img
+                  <AuthenticatedImg
                     src={fileThumbnail}
                     alt={document?.doc_name}
                     className="w-6 h-6 rounded"
diff --git a/web/src/components/image/index.tsx b/web/src/components/image/index.tsx
index 78dbbddd2b..4294efc4d2 100644
--- a/web/src/components/image/index.tsx
+++ b/web/src/components/image/index.tsx
@@ -1,7 +1,6 @@
 import { Authorization } from '@/constants/authorization';
 import { restAPIv1 } from '@/utils/api';
 import { getAuthorization } from '@/utils/authorization-util';
-import { getSearchValue } from '@/utils/common-util';
 import classNames from 'classnames';
 import React, { useEffect, useMemo, useState } from 'react';
 import { Popover, PopoverContent, PopoverTrigger } from '../ui/popover';
@@ -82,19 +81,36 @@ const fetchDocumentImage = (url: string, authorization: string) => {
   };
 };
 
+// Check if a URL requires authentication (internal API URLs)
+// Only attach Authorization headers to same-origin requests to prevent token leakage
+const isAuthRequiredUrl = (url: string): boolean => {
+  try {
+    const parsedUrl = new URL(url, window.location.origin);
+    if (parsedUrl.origin !== window.location.origin) {
+      return false;
+    }
+    return (
+      parsedUrl.pathname.startsWith('/api/v1/') ||
+      parsedUrl.pathname.includes('/documents/images/')
+    );
+  } catch {
+    return false;
+  }
+};
+
 export const useDocumentImageUrl = (id: string, t?: string | number) => {
   const directUrl = useMemo(() => buildDocumentImageUrl(id, t), [id, t]);
-  const [imageUrl, setImageUrl] = useState(() =>
-    getAuthorization() && getSearchValue('shared_id') ? '' : directUrl,
-  );
+  const [imageUrl, setImageUrl] = useState<string>('');
 
   useEffect(() => {
-    const authorization = getAuthorization();
-    if (!authorization || !getSearchValue('shared_id')) {
+    // For non-API URLs (e.g., base64, external URLs), use directly
+    if (!isAuthRequiredUrl(directUrl)) {
       setImageUrl(directUrl);
       return;
     }
 
+    // For API URLs that require authentication, always fetch with auth headers
+    const authorization = getAuthorization();
     let ignore = false;
     setImageUrl('');
     const { promise, release } = fetchDocumentImage(directUrl, authorization);
@@ -120,6 +136,72 @@ export const useDocumentImageUrl = (id: string, t?: string | number) => {
   return imageUrl;
 };
 
+/**
+ * Hook to convert any authenticated URL to a blob URL for use in <img> tags.
+ * Use this for thumbnail URLs or any other API URLs that require authentication.
+ */
+export const useAuthenticatedImageUrl = (url: string | undefined | null) => {
+  const [imageUrl, setImageUrl] = useState<string>('');
+
+  useEffect(() => {
+    if (!url || !isAuthRequiredUrl(url)) {
+      setImageUrl(url || '');
+      return;
+    }
+
+    const authorization = getAuthorization();
+    let cancelled = false;
+    setImageUrl('');
+
+    const { promise, release } = fetchDocumentImage(url, authorization);
+    promise
+      .then((blobUrl) => {
+        if (!cancelled) {
+          setImageUrl(blobUrl);
+        }
+      })
+      .catch(() => {
+        if (!cancelled) {
+          setImageUrl('');
+        }
+      });
+
+    return () => {
+      cancelled = true;
+      release();
+    };
+  }, [url]);
+
+  return imageUrl;
+};
+
+/**
+ * Component that renders an <img> tag with proper authentication for API URLs.
+ * Use this instead of <img src={apiUrl}> when the URL requires authentication.
+ */
+export const AuthenticatedImg = ({
+  src,
+  alt,
+  className,
+  fallback,
+  ...props
+}: React.ImgHTMLAttributes<HTMLImageElement> & {
+  fallback?: React.ReactNode;
+}) => {
+  const authenticatedSrc = useAuthenticatedImageUrl(src);
+
+  if (!authenticatedSrc) return fallback ?? null;
+
+  return (
+    <img
+      src={authenticatedSrc}
+      alt={alt}
+      className={className}
+      {...props}
+    />
+  );
+};
+
 const Image = ({ id, t, label, className, ...props }: IImage) => {
   const src = useDocumentImageUrl(id, t);
   const imageElement = (
diff --git a/web/src/components/markdown-content/index.tsx b/web/src/components/markdown-content/index.tsx
index 7eb6398e37..f33fb745d7 100644
--- a/web/src/components/markdown-content/index.tsx
+++ b/web/src/components/markdown-content/index.tsx
@@ -1,4 +1,4 @@
-import Image from '@/components/image';
+import Image, { AuthenticatedImg } from '@/components/image';
 import SvgIcon from '@/components/svg-icon';
 import { MarkdownRemarkPlugins } from '@/constants/markdown-remark-plugins';
 import { IReference, IReferenceChunk } from '@/interfaces/database/chat';
@@ -203,7 +203,7 @@ const MarkdownContent = ({
             {documentId && (
               <section className="flex gap-1">
                 {fileThumbnail ? (
-                  <img
+                  <AuthenticatedImg
                     src={fileThumbnail}
                     alt=""
                     className={styles.fileThumbnail}
diff --git a/web/src/components/next-markdown-content/index.tsx b/web/src/components/next-markdown-content/index.tsx
index fdd1c5ec93..7fe05a4de9 100644
--- a/web/src/components/next-markdown-content/index.tsx
+++ b/web/src/components/next-markdown-content/index.tsx
@@ -1,4 +1,4 @@
-import Image from '@/components/image';
+import Image, { AuthenticatedImg } from '@/components/image';
 import SvgIcon from '@/components/svg-icon';
 import { MarkdownRemarkPlugins } from '@/constants/markdown-remark-plugins';
 import { IReferenceChunk, IReferenceObject } from '@/interfaces/database/chat';
@@ -296,7 +296,7 @@ function MarkdownContent({
             {documentId && (
               <div className="flex gap-1">
                 {fileThumbnail ? (
-                  <img
+                  <AuthenticatedImg
                     src={fileThumbnail}
                     alt=""
                     className={styles.fileThumbnail}
diff --git a/web/src/pages/next-search/markdown-content/index.tsx b/web/src/pages/next-search/markdown-content/index.tsx
index 577267ebd4..7858fc6edf 100644
--- a/web/src/pages/next-search/markdown-content/index.tsx
+++ b/web/src/pages/next-search/markdown-content/index.tsx
@@ -1,4 +1,4 @@
-import Image from '@/components/image';
+import Image, { AuthenticatedImg } from '@/components/image';
 import SvgIcon from '@/components/svg-icon';
 import { MarkdownRemarkPlugins } from '@/constants/markdown-remark-plugins';
 import { IReference, IReferenceChunk } from '@/interfaces/database/chat';
@@ -185,7 +185,7 @@ const MarkdownContent = ({
             {documentId && (
               <div className="flex gap-2">
                 {fileThumbnail ? (
-                  <img
+                  <AuthenticatedImg
                     src={fileThumbnail}
                     alt=""
                     className={styles.fileThumbnail}