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
"}]}],"references":[{"url":"https://www.ibm.com/support/pages/node/7278595","tags":["vendor-advisory","patch"]}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV3_1":{"version":"3.1","attackVector":"NETWORK","attackComplexity":"HIGH","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH","baseSeverity":"HIGH","baseScore":7.5,"vectorString":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H"}}],"solutions":[{"lang":"en","value":"We recommend customer to enable encryption. Please follow the link to enable encryption.\n https://www.ibm.com/docs/en/wxs/latest?topic=sydgies-securing-data-that-flows-between-extreme-scale-clients-servers-ssl-encryption. \n\nFor extra security customer can enable JEP 290 global JVM deserialization filter (-Djdk.serialFilter) while starting catalog and container servers.JEP 290 is available from 8.0.8.5 onwards.","supportingMedia":[{"type":"text/html","base64":false,"value":"We recommend customer to enable encryption. Please follow the link to enable encryption.
https://www.ibm.com/docs/en/wxs/latest?topic=sydgies-securing-data-that-flows-between-extreme-scale-clients-servers-ssl-encryption.
For extra security customer can enable JEP 290 global JVM deserialization filter (-Djdk.serialFilter) while starting catalog and container servers.JEP 290 is available from 8.0.8.5 onwards.