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
{
"cna_assigner": "eclipse",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/102xxx/CVE-2026-102461.json"
}{
"extracted_events": [
{
"introduced": "4.0.0"
},
{
"last_affected": "4.5.34"
},
{
"introduced": "5.0.0"
},
{
"last_affected": "5.0.12"
},
{
"introduced": "5.1.0"
},
{
"last_affected": "5.1.9"
},
{
"introduced": "5.2.0"
},
{
"last_affected": "5.2.0"
}
],
"source": "AFFECTED_FIELD"
}