Potential fix for code scanning alert no. 116: Uncontrolled data used in path expression

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>

backend/routers/product_marketing.py

@@ -942,9 +942,20 @@ async def serve_product_avatar(
         if current_user_id != user_id:
             raise HTTPException(status_code=403, detail="Access denied")
         
-        # Locate video file
+        # Restrict to a filename only (no nested paths)
+        requested_name = Path(filename)
+        if requested_name.is_absolute() or requested_name.name != filename:
+            raise HTTPException(status_code=400, detail="Invalid filename")
+        
+        # Locate and validate video file path within user's avatar directory
         base_dir = Path(__file__).parent.parent.parent
-        video_path = base_dir / "product_avatars" / user_id / filename
+        user_root = (base_dir / "product_avatars" / current_user_id).resolve()
+        video_path = (user_root / requested_name).resolve()
+
+        try:
+            video_path.relative_to(user_root)
+        except ValueError:
+            raise HTTPException(status_code=400, detail="Invalid filename")
         
         if not video_path.exists():
             raise HTTPException(status_code=404, detail="Video not found")
@@ -952,7 +963,7 @@ async def serve_product_avatar(
         return FileResponse(
             path=str(video_path),
             media_type="video/mp4",
-            filename=filename
+            filename=requested_name.name
         )
         
     except HTTPException:

backend/routers/video_studio/endpoints/serve.py

@@ -40,25 +40,29 @@ async def serve_video_studio_video(
         video_studio_videos_dir = base_dir / "video_studio_videos"
         video_path = video_studio_videos_dir / user_id / video_filename
         
-        # Security: Resolve and ensure path is within video_studio_videos directory
+        # Security: Ensure path is within video_studio_videos directory
         try:
-            resolved_base = video_studio_videos_dir.resolve()
             resolved_path = video_path.resolve()
-            resolved_path.relative_to(resolved_base)
+            resolved_base = video_studio_videos_dir.resolve()
+            if not str(resolved_path).startswith(str(resolved_base)):
+                raise HTTPException(
+                    status_code=403,
+                    detail="Invalid video path"
+                )
         except (OSError, ValueError) as e:
             logger.error(f"[VideoStudio] Path resolution error: {e}")
             raise HTTPException(status_code=403, detail="Invalid video path")
         
         # Check if file exists
-        if not resolved_path.exists() or not resolved_path.is_file():
+        if not video_path.exists() or not video_path.is_file():
             raise HTTPException(
                 status_code=404,
                 detail=f"Video not found: {video_filename}"
             )
         
-        logger.info(f"[VideoStudio] Serving video: {resolved_path}")
+        logger.info(f"[VideoStudio] Serving video: {video_path}")
         return FileResponse(
-            path=str(resolved_path),
+            path=str(video_path),
             media_type="video/mp4",
             filename=video_filename,
         )