Description
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.
Affected products
shamaton: msgpack
References4
- github.com/shamaton/msgpack/issues/59 Issue TrackingVendor Advisory
- securityinfinity.com/research/shamaton-msgpack-oob-panic-fixext… ExploitThird Party Advisory
- github.com/golang/vulndb/issues/4513 Issue TrackingThird Party Advisory
- pkg.go.dev/vuln/GO-2026-4513 Third Party Advisory
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 38 · as of 12 November 2026
- CWE
- CWE-125
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