CVE-2026-90472: msgpack-java through 0.9.12 Stack Overflow via Nested Arrays

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-12 · updated 2026-09-23
Weakness: CWE-674

Description

msgpack-java through 0.9.12 contains a stack overflow vulnerability in MessageUnpacker.unpackValue() that recursively deserializes arrays and maps without nesting depth limits. Attackers can craft payloads with deeply nested arrays to exhaust the deserializing thread's stack and trigger StackOverflowError, causing per-request deserialization failures.

Affected products

msgpack-java: through 0.9.12

References

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#L646-L664
https://github.com/msgpack/msgpack-java/issues/1015
https://www.vulncheck.com/advisories/msgpack-java-through-0.9.12-stack-overflow-via-nested-arrays
https://github.com/msgpack/msgpack-java/issues/1015

Get alerted when CVE-2026-90472 or the next vulnerability affects your stack