CVE-2026-13759

CVE-2026-13759 affects IBM WebSphere eXtreme Scale (WebSphere Extreme Scale) 8.6.1.0–8.6.1.6. The root cause is insecure deserialization: three ObjectInputStream subclasses (WsObjectInputStream, ObjectStreamPool$ReusableInputStream, ObjectInputStreamResolver) ship without a JEP-290 class filter. ...

CVE-2026-13759: Deserialization of Untrusted Data

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...