CVE-2026-13772: IBM WebSphere Extreme Scale

Critical severity, CVSS 9.9. EPSS: 0.5% chance of exploitation in the next 30 days.

IBM WebSphere Extreme Scale 8.6.1.0 through 8.6.1.6 's Object Query Language engine resolves attacker-supplied class names via Class.forName() and invokes their constructors with no allow-list at three distinct sinks (SELECT NEW, enum literals, and reflection-based comparators); an authenticated remote attacker who can influence an application-built OQL query string can execute arbitrary constructors on the WAS JVM, and a SELECT DISTINCT variant using planted grid values fires the same gadget post-readObject in a manner that survives JEP-290 serialization filters across grid node boundaries

Affected products

• IBM WebSphere Extreme Scale: from 8.6.1.0, up to and including 8.6.1.6

Published 2026-06-30. Last modified 2026-07-03.