CVE-2026-13759

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

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.6 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.ibm.com/support/pages/node/7278595	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:ibm:websphere_extreme_scale:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-06-30 20:17

Updated : 2026-07-03 04:17

NVD link : CVE-2026-13759

Mitre link : CVE-2026-13759

CVE.ORG link : CVE-2026-13759

JSON object : View

Products Affected

ibm

websphere_extreme_scale

CWE

CWE-502

Deserialization of Untrusted Data

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