CVE-2026-32284

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/golang/vulndb/issues/4513	Issue Tracking Third Party Advisory
https://github.com/shamaton/msgpack/issues/59	Issue Tracking Vendor Advisory
https://pkg.go.dev/vuln/GO-2026-4513	Third Party Advisory
https://securityinfinity.com/research/shamaton-msgpack-oob-panic-fixext-dos-2026	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:shamaton:msgpack:*:*:*:*:*:go:*:*

History

No history.

Information

Published : 2026-03-26 20:16

Updated : 2026-06-17 10:35

NVD link : CVE-2026-32284

Mitre link : CVE-2026-32284

CVE.ORG link : CVE-2026-32284

JSON object : View

Products Affected

shamaton

msgpack

CWE

CWE-125

Out-of-bounds Read

{"id": "CVE-2026-32284", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-32284", "role": "CISA Coordinator", "options": [{"exploitation": "poc"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-03-30T14:04:12.686407Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.5, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 3.9}]}, "affected": [{"source": "security@golang.org", "affectedData": [{"vendor": "github.com/shamaton/msgpack", "product": "github.com/shamaton/msgpack", "packageName": "github.com/shamaton/msgpack", "collectionURL": "https://pkg.go.dev", "defaultStatus": "affected", "programRoutines": [{"name": "Unmarshal"}, {"name": "UnmarshalAsMap"}, {"name": "UnmarshalAsArray"}, {"name": "DecodeStructAsArray"}, {"name": "DecodeStructAsMap"}]}, {"vendor": "github.com/shamaton/msgpack/v2", "product": "github.com/shamaton/msgpack/v2", "packageName": "github.com/shamaton/msgpack/v2", "collectionURL": "https://pkg.go.dev", "defaultStatus": "affected", "programRoutines": [{"name": "Unmarshal"}, {"name": "UnmarshalAsMap"}, {"name": "UnmarshalAsArray"}]}, {"vendor": "github.com/shamaton/msgpack/v3", "product": "github.com/shamaton/msgpack/v3", "packageName": "github.com/shamaton/msgpack/v3", "collectionURL": "https://pkg.go.dev", "defaultStatus": "affected", "programRoutines": [{"name": "Unmarshal"}, {"name": "UnmarshalAsMap"}, {"name": "UnmarshalAsArray"}]}]}], "published": "2026-03-26T20:16:12.087", "references": [{"url": "https://github.com/golang/vulndb/issues/4513", "tags": ["Issue Tracking", "Third Party Advisory"], "source": "security@golang.org"}, {"url": "https://github.com/shamaton/msgpack/issues/59", "tags": ["Issue Tracking", "Vendor Advisory"], "source": "security@golang.org"}, {"url": "https://pkg.go.dev/vuln/GO-2026-4513", "tags": ["Third Party Advisory"], "source": "security@golang.org"}, {"url": "https://securityinfinity.com/research/shamaton-msgpack-oob-panic-fixext-dos-2026", "tags": ["Exploit", "Third Party Advisory"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-125"}]}], "descriptions": [{"lang": "en", "value": "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."}, {"lang": "es", "value": "El decodificador msgpack no valida correctamente la longitud del b\u00fafer de entrada al procesar datos fixext truncados (c\u00f3digos de formato 0xd4-0xd8). Esto puede provocar una lectura fuera de l\u00edmites y un p\u00e1nico en tiempo de ejecuci\u00f3n, lo que permite un ataque de denegaci\u00f3n de servicio."}], "lastModified": "2026-06-17T10:35:29.407", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:shamaton:msgpack:*:*:*:*:*:go:*:*", "vulnerable": true, "matchCriteriaId": "E3EFFC2E-A452-4815-B2AC-3AD7CD6828D3", "versionEndIncluding": "3.1.2"}], "operator": "OR"}]}], "sourceIdentifier": "security@golang.org"}