diff --git a/frontend/components/AuthenticatedFilePreview.client.vue b/frontend/components/AuthenticatedFilePreview.client.vue
new file mode 100644
index 0000000..be51aed
--- /dev/null
+++ b/frontend/components/AuthenticatedFilePreview.client.vue
@@ -0,0 +1,84 @@
+<script setup lang="ts">
+import { onBeforeUnmount, ref, watch } from "vue"
+
+const props = defineProps<{
+  fileId: string
+  path?: string | null
+}>()
+
+const { $api } = useNuxtApp()
+const objectUrl = ref<string | null>(null)
+const loadFailed = ref(false)
+
+const isPdf = computed(() => String(props.path || "").toLowerCase().endsWith(".pdf"))
+
+const revokeObjectUrl = () => {
+  if (!objectUrl.value) return
+  URL.revokeObjectURL(objectUrl.value)
+  objectUrl.value = null
+}
+
+const loadFile = async () => {
+  revokeObjectUrl()
+  loadFailed.value = false
+
+  try {
+    const blob = await $api<Blob>(`/api/files/content/${encodeURIComponent(props.fileId)}`, {
+      responseType: "blob"
+    })
+    objectUrl.value = URL.createObjectURL(blob)
+  } catch (error) {
+    loadFailed.value = true
+    console.error("Dateivorschau konnte nicht geladen werden:", error)
+  }
+}
+
+watch(() => props.fileId, loadFile, { immediate: true })
+onBeforeUnmount(revokeObjectUrl)
+</script>
+
+<template>
+  <div class="authenticated-file-preview">
+    <iframe
+        v-if="objectUrl && isPdf"
+        :src="`${objectUrl}#toolbar=0&navpanes=0&scrollbar=0`"
+        title="PDF-Vorschau"
+        loading="lazy"
+    />
+    <img v-else-if="objectUrl" :src="objectUrl" alt="Dateivorschau" />
+    <div v-else-if="loadFailed" class="preview-placeholder">
+      <UIcon name="i-heroicons-document" class="h-10 w-10" />
+      <span>Keine Vorschau verfügbar</span>
+    </div>
+    <USkeleton v-else class="h-full min-h-32 w-full" />
+  </div>
+</template>
+
+<style scoped>
+.authenticated-file-preview,
+.authenticated-file-preview iframe,
+.authenticated-file-preview img {
+  width: 100%;
+  height: 100%;
+}
+
+.authenticated-file-preview iframe {
+  border: 0;
+  pointer-events: none;
+}
+
+.authenticated-file-preview img {
+  object-fit: contain;
+}
+
+.preview-placeholder {
+  display: flex;
+  min-height: 8rem;
+  flex-direction: column;
+  align-items: center;
+  justify-content: center;
+  gap: 0.5rem;
+  color: rgb(107 114 128);
+  font-size: 0.875rem;
+}
+</style>
diff --git a/frontend/components/DocumentDisplay.vue b/frontend/components/DocumentDisplay.vue
index 6db5d5a..e901480 100644
--- a/frontend/components/DocumentDisplay.vue
+++ b/frontend/components/DocumentDisplay.vue
@@ -38,16 +38,10 @@ const showFile = (file) => {
 
 <template>
   <div :id="`docDisplay-${documentData.id}`"  class="documentListItem" @click="returnEmit ? $emit('clicked', documentData.id) : showFile(documentData)">
-    <iframe
-        :src="`${documentData.url}#toolbar=0&navpanes=0&scrollbar=0`"
+    <AuthenticatedFilePreview
+        :file-id="documentData.id"
+        :path="documentData.path"
         class="previewEmbed"
-        v-if="documentData.path.toLowerCase().includes('pdf')"
-        loading="lazy"
-    />
-    <img
-      v-else
-      alt=""
-      :src="documentData.url"
     />
 <!-- TODO: Remove Scrollbar    -->
     <UTooltip class="w-full" :text="documentData.path.split('/')[documentData.path.split('/').length -1]">
@@ -92,4 +86,4 @@ const showFile = (file) => {
   display: none;
 }
 
-</style>
\ No newline at end of file
+</style>
diff --git a/frontend/components/DocumentDisplayModal.vue b/frontend/components/DocumentDisplayModal.vue
index cad77bc..808a18c 100644
--- a/frontend/components/DocumentDisplayModal.vue
+++ b/frontend/components/DocumentDisplayModal.vue
@@ -1,6 +1,7 @@
 <script setup>
 const toast = useToast()
 const modal = useModal()
+const fileService = useFiles()
 
 const props = defineProps({
   documentData: {
@@ -68,6 +69,15 @@ const archiveDocument = async () => {
   await updateDocument({archived: true}, true)
 }
 
+const openDocument = async () => {
+  try {
+    await fileService.openFile(props.documentData.id)
+  } catch (error) {
+    console.error(error)
+    toast.add({title: "Datei konnte nicht geöffnet werden", color: "error"})
+  }
+}
+
 const getItemsBySelectedResource = async () => {
   idToAssign.value = null
   itemOptions.value = selectedResource.value?.entity
@@ -155,11 +165,11 @@ setup()
                 v-if="props.documentData.id && String(props.documentData.path || '').toLowerCase().includes('pdf')"
                 :file-id="props.documentData.id" />
 
-            <img
+            <AuthenticatedFilePreview
                 v-else
                 class="w-full"
-                :src="props.documentData.url"
-                alt=""
+                :file-id="props.documentData.id"
+                :path="props.documentData.path"
             />
           </div>
 
@@ -173,10 +183,9 @@ setup()
               />
 
               <UButton
-                  :to="props.documentData.url"
+                  @click="openDocument"
                   variant="outline"
                   icon="i-heroicons-arrow-top-right-on-square"
-                  target="_blank"
               >
                 Öffnen
               </UButton>
diff --git a/frontend/components/EntityShowSubFiles.vue b/frontend/components/EntityShowSubFiles.vue
index 4553e81..43e4c0e 100644
--- a/frontend/components/EntityShowSubFiles.vue
+++ b/frontend/components/EntityShowSubFiles.vue
@@ -119,8 +119,9 @@ function isImage(file) {
             v-else-if="activeFile && isImage(activeFile)"
             class="p-4 flex justify-center"
         >
-          <img
-              :src="activeFile.url"
+          <AuthenticatedFilePreview
+              :file-id="activeFile.id"
+              :path="activeFile.path"
               class="max-w-full max-h-[80vh] rounded-lg shadow"
           />
         </div>
diff --git a/frontend/composables/useFiles.ts b/frontend/composables/useFiles.ts
index 7abb3dc..6baea2f 100644
--- a/frontend/composables/useFiles.ts
+++ b/frontend/composables/useFiles.ts
@@ -146,6 +146,26 @@ export const useFiles = () => {
 
     }
 
+    const openFile = async (id: string) => {
+        const targetWindow = window.open("about:blank", "_blank")
+
+        try {
+            const blob = await downloadFile(id, undefined, true) as Blob
+            const objectUrl = URL.createObjectURL(blob)
+
+            if (targetWindow) {
+                targetWindow.location.replace(objectUrl)
+            } else {
+                window.open(objectUrl, "_blank")
+            }
+
+            window.setTimeout(() => URL.revokeObjectURL(objectUrl), 60_000)
+        } catch (error) {
+            targetWindow?.close()
+            throw error
+        }
+    }
+
     const dataURLtoFile = (dataurl:string, filename:string) => {
         let arr = dataurl.split(","),
             //@ts-ignore
@@ -160,5 +180,5 @@ export const useFiles = () => {
     }
 
 
-    return {uploadFiles, selectDocuments, selectSomeDocuments, selectDocument, downloadFile, dataURLtoFile}
+    return {uploadFiles, selectDocuments, selectSomeDocuments, selectDocument, downloadFile, openFile, dataURLtoFile}
 }