Bug 2532555 (CVE-2026-90473)

Summary: CVE-2026-90473 org.msgpack/msgpack-core: msgpack-java: Information disclosure via integer overflow in MessageUnpacker.skipValue()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: gmalinko, janstey, pdelbell, rstepani
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: ---
Doc Text:
A flaw was found in msgpack-java. An integer overflow vulnerability exists in the `MessageUnpacker.skipValue()` function when processing `MAP32` containers with a large number of elements. A remote attacker can exploit this by supplying a `MAP32` element count that causes an integer wrap-around, leading to a desynchronization of the parser cursor. This can result in attacker-controlled data being returned in place of legitimate fields, potentially leading to information disclosure.
 Story Points: ---
Clone Of: Environment:
Last Closed: Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-09-12 11:21:25 UTC 
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.