fix(run-server): handle malformed JSON frames without crashing#40121
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yury-s wants to merge 1 commit intomicrosoft:mainfrom
Open
fix(run-server): handle malformed JSON frames without crashing#40121yury-s wants to merge 1 commit intomicrosoft:mainfrom
yury-s wants to merge 1 commit intomicrosoft:mainfrom
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A malformed WebSocket text frame caused JSON.parse to throw an uncaught SyntaxError from the async message listener, terminating the run-server process. Catch the parse error, close the offending connection with code 1007, and keep the server running.
Contributor
Test results for "tests 1"8 flaky39196 passed, 846 skipped Merge workflow run. |
Contributor
Test results for "MCP"6468 passed, 383 skipped Merge workflow run. |
pavelfeldman
approved these changes
Apr 10, 2026
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Summary
run-servercrashed on a single malformed WebSocket text frame becauseJSON.parsein the message listener was unprotected, turning aSyntaxErrorinto an unhandled rejection that terminated the process — a pre-auth DoS when the endpoint is exposed beyond localhost.1007(invalid frame payload data), and keep the server running.]on a raw WebSocket and then reconnects viabrowserType.connectto verify the server is still alive.