diff --git a/lib/Chat/Parser/SystemMessage.php b/lib/Chat/Parser/SystemMessage.php
index d70bb56bfa1..30ceaba620d 100644
--- a/lib/Chat/Parser/SystemMessage.php
+++ b/lib/Chat/Parser/SystemMessage.php
@@ -800,11 +800,11 @@ protected function getFileFromShare(?Participant $participant, string $shareId):
 			'type' => 'file',
 			'id' => (string) $fileId,
 			'name' => $name,
-			'size' => $size,
+			'size' => (string) $size,
 			'path' => $path,
 			'link' => $url,
 			'etag' => $node->getEtag(),
-			'permissions' => $node->getPermissions(),
+			'permissions' => (string) $node->getPermissions(),
 			'mimetype' => $node->getMimeType(),
 			'preview-available' => $isPreviewAvailable ? 'yes' : 'no',
 		];
@@ -814,8 +814,8 @@ protected function getFileFromShare(?Participant $participant, string $shareId):
 			try {
 				$sizeMetadata = $this->metadataCache->getMetadataPhotosSizeForFileId($fileId);
 				if (isset($sizeMetadata['width'], $sizeMetadata['height'])) {
-					$data['width'] = $sizeMetadata['width'];
-					$data['height'] = $sizeMetadata['height'];
+					$data['width'] = (string) $sizeMetadata['width'];
+					$data['height'] = (string) $sizeMetadata['height'];
 				}
 			} catch (FilesMetadataNotFoundException) {
 			}
diff --git a/src/components/MessagesList/MessagesGroup/Message/MessagePart/FilePreview.vue b/src/components/MessagesList/MessagesGroup/Message/MessagePart/FilePreview.vue
index 08865087388..da9f4ac00e2 100644
--- a/src/components/MessagesList/MessagesGroup/Message/MessagePart/FilePreview.vue
+++ b/src/components/MessagesList/MessagesGroup/Message/MessagePart/FilePreview.vue
@@ -153,8 +153,8 @@ export default {
 		 * File size in bytes
 		 */
 		size: {
-			type: Number,
-			default: -1,
+			type: String,
+			default: '-1',
 		},
 		/**
 		 * Download link
@@ -181,8 +181,8 @@ export default {
 		 * File ETag
 		 */
 		permissions: {
-			type: Number,
-			default: 0,
+			type: String,
+			default: '0',
 		},
 		/**
 		 * Whether a preview is available, string "yes" for yes
@@ -198,7 +198,7 @@ export default {
 		 * If preview and metadata are available, return width
 		 */
 		width: {
-			type: Number,
+			type: String,
 			default: null,
 		},
 
@@ -206,7 +206,7 @@ export default {
 		 * If preview and metadata are available, return height
 		 */
 		height: {
-			type: Number,
+			type: String,
 			default: null,
 		},
 
@@ -407,12 +407,12 @@ export default {
 			}
 
 			const sizeMultiplicator = Math.min(
-				(heightConstraint > this.height ? 1 : (heightConstraint / this.height)),
-				(widthConstraint > this.width ? 1 : (widthConstraint / this.width))
+				(heightConstraint > parseInt(this.height, 10) ? 1 : (heightConstraint / parseInt(this.height, 10))),
+				(widthConstraint > parseInt(this.width, 10) ? 1 : (widthConstraint / parseInt(this.width, 10)))
 			)
 
 			return {
-				width: this.width * sizeMultiplicator + 'px',
+				width: parseInt(this.width, 10) * sizeMultiplicator + 'px',
 				aspectRatio: this.width + '/' + this.height,
 			}
 		},
@@ -426,7 +426,7 @@ export default {
 				return PREVIEW_TYPE.MIME_ICON
 			}
 			const maxGifSize = getCapabilities()?.spreed?.config?.previews?.['max-gif-size'] || 3145728
-			if (this.mimetype === 'image/gif' && this.size <= maxGifSize) {
+			if (this.mimetype === 'image/gif' && parseInt(this.size, 10) <= maxGifSize) {
 				return PREVIEW_TYPE.DIRECT
 			}
 
diff --git a/src/types/index.ts b/src/types/index.ts
index 02c31e34125..4f40e6e4a80 100644
--- a/src/types/index.ts
+++ b/src/types/index.ts
@@ -43,9 +43,9 @@ export type Participant = components['schemas']['Participant']
 export type Mention = RichObject<'server'|'call-type'|'icon-url'>
 export type File = RichObject<'size'|'path'|'link'|'mimetype'|'preview-available'> & {
 	'etag': string,
-	'permissions': number,
-	'width': number,
-	'height': number,
+	'permissions': string,
+	'width': string,
+	'height': string,
 }
 export type ChatMessage = components['schemas']['ChatMessageWithParent']
 export type receiveMessagesParams = ApiOptions<operations['chat-receive-messages']['parameters']['query']>['params']
diff --git a/tests/php/Chat/Parser/SystemMessageTest.php b/tests/php/Chat/Parser/SystemMessageTest.php
index ae4ea08058a..269643705c9 100644
--- a/tests/php/Chat/Parser/SystemMessageTest.php
+++ b/tests/php/Chat/Parser/SystemMessageTest.php
@@ -679,15 +679,15 @@ public function testGetFileFromShareForGuest() {
 			'type' => 'file',
 			'id' => '54',
 			'name' => 'name',
-			'size' => 65530,
+			'size' => '65530',
 			'path' => 'name',
 			'link' => 'absolute-link',
 			'etag' => '1872ade88f3013edeb33decd74a4f947',
-			'permissions' => 27,
+			'permissions' => '27',
 			'mimetype' => 'image/png',
 			'preview-available' => 'yes',
-			'width' => 1234,
-			'height' => 4567,
+			'width' => '1234',
+			'height' => '4567',
 		], self::invokePrivate($parser, 'getFileFromShare', [$participant, '23']));
 	}
 
@@ -760,11 +760,11 @@ public function testGetFileFromShareForOwner() {
 			'type' => 'file',
 			'id' => '54',
 			'name' => 'name',
-			'size' => 65520,
+			'size' => '65520',
 			'path' => 'path/to/file/name',
 			'link' => 'absolute-link-owner',
 			'etag' => '1872ade88f3013edeb33decd74a4f947',
-			'permissions' => 27,
+			'permissions' => '27',
 			'mimetype' => 'httpd/unix-directory',
 			'preview-available' => 'no',
 		], self::invokePrivate($parser, 'getFileFromShare', [$participant, '23']));
@@ -847,11 +847,11 @@ public function testGetFileFromShareForRecipient() {
 			'type' => 'file',
 			'id' => '54',
 			'name' => 'different',
-			'size' => 65515,
+			'size' => '65515',
 			'path' => 'Shared/different',
 			'link' => 'absolute-link-owner',
 			'etag' => '1872ade88f3013edeb33decd74a4f947',
-			'permissions' => 27,
+			'permissions' => '27',
 			'mimetype' => 'application/octet-stream',
 			'preview-available' => 'no',
 		], self::invokePrivate($parser, 'getFileFromShare', [$participant, '23']));