CVE-2026-90473

15th percentile - higher than 15% of all known CVEs

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.

The vulnerability can lead to parser desynchronization and return of incorrect data, potentially resulting in data misinterpretation or further attacks. It affects the integrity of processed data.

Update the msgpack-java library to a version later than 0.9.12. Until then, consider validating MAP32 container sizes before deserialization.