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Miggo AIRoot Cause AnalysisThe vulnerability lies in the aiohttp.web_response.Response.write_eof function. The provided patch clearly shows that the original implementation did not correctly handle exceptions during the writing of a response body (Payload). If an error occurred during self._body.write(), for instance, due to a client disconnecting, the self._body.close() method was never called. This could lead to resource leaks, as file handles or other resources held by the payload object would not be released. The fix involves wrapping the write() call in a try...finally block, which ensures that close() is always called, regardless of whether write() succeeds or fails. The associated test cases added in the patch further confirm this by simulating write errors and cancellations to verify that the payload's close() method is indeed called in all scenarios.
Response.write_eofaiohttp/web_response.py
| Package Name | Ecosystem | Vulnerable Versions | First Patched Version |
|---|---|---|---|
| aiohttp | pip | <= 3.14.0 | 3.14.1 |