diff --git a/packages/server/src/utils/createAttachment.ts b/packages/server/src/utils/createAttachment.ts
index 9e9228f15..10495140d 100644
--- a/packages/server/src/utils/createAttachment.ts
+++ b/packages/server/src/utils/createAttachment.ts
@@ -32,7 +32,7 @@ export const createFileAttachment = async (req: Request) => {
     if (!chatflowid || !isValidUUID(chatflowid)) {
         throw new InternalFlowiseError(StatusCodes.BAD_REQUEST, 'Invalid chatflowId format - must be a valid UUID')
     }
-    if (isPathTraversal(chatflowid) || isPathTraversal(chatId)) {
+    if (isPathTraversal(chatflowid) || (chatId && isPathTraversal(chatId))) {
         throw new InternalFlowiseError(StatusCodes.BAD_REQUEST, 'Invalid path characters detected')
     }