CVE-2026-102461: Maven/io.vertx/vertx-json-schema vulnerability
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 Software
Event History
Frequently Asked Questions
What must an attacker be able to do to trigger the issue?
An attacker must be able to remotely submit an unauthenticated JSON array to a validation path that evaluates the uniqueItems keyword. A moderately sized array can cause disproportionate CPU consumption.
Which Vert.x components should be reviewed for exposure?
Review direct use of io.vertx:vertx-json-schema and use of io.vertx:vertx-web-openapi-router, io.vertx:vertx-web-validation, or io.vertx:vertx-openapi. The listed modules depend on vertx-json-schema and are also affected.
Which release ranges are affected?
Affected releases are Vert.x 4.0.0 through 4.5.34, 5.0.0 through 5.0.12, 5.1.0 through 5.1.9, and 5.2.0.