Description
The reserved MessagePack byte 0xc1 is incorrectly treated as incomplete input. When it appears at the start of a decoder stream, all subsequent data is retained while the decoder waits for bytes that can never make the value valid, allowing memory exhaustion.
Recommendation
Update the msgpack5 package to the latest compatible version. Followings are version details:
- Affected version(s): < 6.1.0
- Patched version(s): 6.1.0
References
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See something that needs correcting? Let us knowUpdated October 08, 2026