🛡️ Sentinel: [MEDIUM] Fix information leakage in ingest route

.jules/sentinel.md

@@ -6,3 +6,8 @@
 **Vulnerability:** The custom `SafeStaticFiles` middleware in `src/audioformation/server/app.py` intended to block access to sensitive directories (like `00_CONFIG` and `.git`). However, it used `p = Path(path).lower()`, which raises an `AttributeError` because `pathlib.Path` objects lack a `.lower()` method. This effectively broke static file serving entirely (causing 500 errors) and represented a malformed security check. If such errors were ever 'swallowed' without raising an HTTP exception, it could result in 'failing open' and allowing access to sensitive files.
 **Learning:** Security checks that rely on path manipulation or normalization must be carefully tested for runtime exceptions. An unhandled exception in a security gate can either block legitimate traffic (Denial of Service) or, if caught improperly elsewhere, fail open. Always normalize the string representation of paths before converting them to `Path` objects.
 **Prevention:** Thoroughly test security middleware endpoints for both valid and invalid access attempts. Ensure that path string normalizations like `.lower()` are applied directly to the string before instantiating `Path(str(path).lower())`.
+
+## 2025-02-27 - Information Leakage via HTTP 500 Responses
+**Vulnerability:** The application was exposing the raw exception string (e.g. `f"Upload failed: {e}"`) in HTTP 500 error responses returned to the user in `routes.py`, potentially leaking internal system details.
+**Learning:** Returning unhandled exception strings directly to the client is a security risk. FastAPI exception handlers should "fail closed" by logging the exact error message internally (`logger.error()`) for debugging but displaying a safe, generic message (like `Upload failed`) to the user.
+**Prevention:** In API endpoints, explicitly catch specific exceptions where possible. Use structured logging to capture context, and standardize `HTTPException` details to generic, unrevealing descriptions for HTTP 500 errors.

src/audioformation/server/routes.py

@@ -185,7 +185,8 @@ async def ingest_files(
                 shutil.copyfileobj(file.file, buffer)
     except Exception as e:
         shutil.rmtree(tmp_dir, ignore_errors=True)
-        raise HTTPException(status_code=500, detail=f"Upload failed: {e}")
+        logger.error(f"Upload failed: {e}")
+        raise HTTPException(status_code=500, detail="Upload failed")
 
     background_tasks.add_task(
         _run_with_status,