7.5
High
CVE-2026-13759 IBM WebSphere Extreme Scale 8.6.1.0 through 8.6.1.6 ships three ObjectInputStream subclasses (WsObjectInputStream,…
Description
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 products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| WebSphere eXtreme Scale 8.6 | 8.6.1.0 → 8.6.1.6 | No fix stated |
Other CVEs of WebSphere eXtreme Scale
The 9 CVEs of WebSphere eXtreme Scale →
CVE-2026-13772
IBM WebSphere Extreme Scale 8.6.1.0 through 8.6.1.6 's Object Query Language engine resolves attacker-supplied class…
7.5
High
CVE-2026-13773
IBM WebSphere Extreme Scale 8.6.1.0 through 8.6.1.6 Approximately 50 generated CORBA stub classes in WebSphere eXtreme…
6.0
Medium
CVE-2026-9002
IBM WebSphere Extreme Scale 8.6.1.0 through 8.6.1.6 could allow an adjacent attacker to cause a denial of service due to…
6.5
Medium
CVE-2020-4336
IBM WebSphere eXtreme Scale 8.6.1 stores sensitive information in URL parameters
3.7
Low