GHSA-h9q6-hc68-35rp: Denial of service in github.com/shamaton/msgpack

March 18, 2026

The msgpack decoder fails to properly validate the input buffer length when processing truncated fixext data (format codes 0xd4-0xd8). This can lead to an out-of-bounds read and a runtime panic, allowing a denial of service attack.

References

github.com/advisories/GHSA-h9q6-hc68-35rp
github.com/golang/vulndb/issues/4513
github.com/shamaton/msgpack
github.com/shamaton/msgpack/issues/59
securityinfinity.com/research/shamaton-msgpack-oob-panic-fixext-dos-2026

Code Behaviors & Features

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