CVE-2026-13759

published 2026-06-30

CVE-2026-13759: IBM WebSphere Extreme Scale 8.6.1.0 through 8.6.1.6 ships three ObjectInputStream subclasses (WsObjectInputStream, ObjectStreamPool$ReusableInputStream…

Priority P3 57 high 8.8 CVSS 3.1

AV N AC L PR L UI N S U C H I H A H

IBM WebSphere Extreme Scale 8.6.1.0 through 8.6.1.6 ships three ObjectInputStream subclasses (WsObjectInputStream, ObjectStreamPool$ReusableInputStream, ObjectInputStreamResolver) that install no JEP-290 class filter; when Coherence is on the classpath, multiple RCE gadget chains including RemoteConstructor.readResolve and PriorityQueue/ExtractorComparator are confirmed working, allowing a post-login attacker who can write a session attribute or a LAN-adjacent attacker on the grid replication wire to execute arbitrary code on peer WAS JVMs

Affected

1 ranges

Vendor	Product	Version range	Fixed in
ibm	websphere_extreme_scale	8.6.1.0 – 8.6.1.6	—

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