| Package | Affected versions | Patched versions |
|---|---|---|
| undici | ≥ 7.0.0, < 7.24.0< 6.24.0 | 7.24.06.24.0 |
| undici | ≥ 7.0.0, < 7.24.0< 6.24.0 | 7.24.06.24.0 |
The undici WebSocket client is vulnerable to a denial-of-service attack due to improper validation of the server_max_window_bits parameter in the permessage-deflate extension. When a WebSocket client connects to a server, it automatically advertises support for permessage-deflate compression. A malicious server can respond with an out-of-range server_max_window_bits value (outside zlib's valid range of 8-15). When the server subsequently sends a compressed frame, the client attempts to create a zlib InflateRaw instance with the invalid windowBits value, causing a synchronous RangeError exception that is not caught, resulting in immediate process termination.
The vulnerability exists because:
isValidClientWindowBits() function only validates that the value contains ASCII digits, not that it falls within the valid range 8-15createInflateRaw() call is not wrapped in a try-catch blockHas the problem been patched? What versions should users upgrade to?
Is there a way for users to fix or remediate the vulnerability without upgrading?
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