🛡️ Sentinel: [MEDIUM] Fix exception string leakage in HTTP responses

.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())`.
+
+## 2025-05-25 - Prevent Exception String Leakage in API Routes
+**Vulnerability:** The raw string representation of caught internal exceptions (`Exception as e`) was being exposed directly to clients inside HTTP 500 responses (e.g., `raise HTTPException(status_code=500, detail=f"Upload failed: {e}")`).
+**Learning:** This exposes sensitive internal application state, stack details, or potentially infrastructure specifics (like file paths or database queries) to external users, enabling reconnaissance for further attacks.
+**Prevention:** Always log the exception details internally using `logger.error` or `logger.exception` and return a generic, static message to the client (e.g., `"Upload failed"` or `"Internal server error"`).

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 for project {project_id}: {e}")
+        raise HTTPException(status_code=500, detail="Upload failed")
 
     background_tasks.add_task(
         _run_with_status,