CVE-2026-90473

msgpack-java through 0.9.12 contains an integer overflow vulnerability in MessageUnpacker.skipValue() when processing MAP32 containers with large element counts. Attackers can supply a MAP32 element count at or above 0x40000000 that wraps when doubled, causing the parser cursor to desynchronize and attacker-controlled data to be returned in place of later fields.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/msgpack/msgpack-java
https://github.com/msgpack/msgpack-java/blob/v0.9.12/msgpack-core/src/main/java/org/msgpack/core/MessageUnpacker.java#L573-L581
https://github.com/msgpack/msgpack-java/issues/1014
https://www.vulncheck.com/advisories/msgpack-java-through-0.9.12-integer-overflow-via-map32

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-12 11:16

Updated : 2026-09-12 11:16

NVD link : CVE-2026-90473

Mitre link : CVE-2026-90473

CVE.ORG link : CVE-2026-90473

JSON object : View

Products Affected

No product.

CWE

CWE-190

Integer Overflow or Wraparound

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