Vulnerability in Msgpack Msgpack-Java
CVE-2026-90472
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.
EPSS exploit prediction
EPSS: 0.006 (46.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 47th percentile — 46.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000
Affected products
Weakness classification (CWE)
References
- github.com/msgpack/msgpack-java (product)
- github.com/msgpack/msgpack-java/blob/v0.9.12/msgpack-core/src/main/java/org/msg… (technical-description)
- github.com/msgpack/msgpack-java/issues/1015 (issue-tracking)
- www.vulncheck.com/advisories/msgpack-java-through-0.9.12-stack-overflow-via-nes… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-90472?
- CVE-2026-90472 is a medium-severity vulnerability in Msgpack Msgpack-Java, classified under Uncontrolled Recursion. CVSS score: 5.3/10. Published 2026-09-12.
- How severe is CVE-2026-90472?
- Medium severity. CVSS v3 base score is 5.3 out of 10.