CVE-2026-102461: Eclipse Foundation Eclipse Vert.x

High severity, CVSS 8.7. EPSS: 0.4% chance of exploitation in the next 30 days.

In Eclipse Vert.x versions [4.0.0, 4.5.34] or [5.0.0,5.0.12] or [5.1.0,5.1.9] or [5.2.0, 5.2.0], the uniqueItems keyword validation uses an O(n²) pairwise comparison loop with no short-circuit or size limit. A remote unauthenticated attacker can submit a moderately-sized JSON array that consumes disproportionate CPU time, leading to denial of service. The impacted component is io.vertx:vertx-json-schema. The following Vert.x modules depend on vertx-json-schema and are also affected: io.vertx:vertx-web-openapi-router io.vertx:vertx-web-validation io.vertx:vertx-openapi

Affected products

• Eclipse Foundation Eclipse Vert.x: from 4.0.0, up to and including 4.5.34; from 5.0.0, up to and including 5.0.12; from 5.1.0, up to and including 5.1.9; version 5.2.0 only

Published 2026-10-15. Last modified 2026-10-16.