---
id: CVE-2026-102461
title: >-
  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
summary: >-
  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
  atta…
severity: high
cvss: 8.7
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'
vendor: Eclipse Foundation
product: Eclipse Vert.x
affected:
  - eclipse_vert.x >= 4.0.0 <= 4.5.34
  - eclipse_vert.x >= 5.0.0 <= 5.0.12
  - eclipse_vert.x >= 5.1.0 <= 5.1.9
  - eclipse_vert.x 5.2.0
published: '2026-10-15'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T09:17:14.887'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-102461'
references:
  - url: >-
      https://github.com/eclipse-vertx/vertx-json-schema/security/advisories/GHSA-4m87-8qfr-8p8m
    label: emo@eclipse.org
  - url: 'https://gitlab.eclipse.org/security/cve-assignment/-/work_items/340'
    label: emo@eclipse.org
tags:
  - nvd
  - cve.org
cvssSource: cna
ingestedAt: '2026-10-15T08:58:33.099Z'
---

## Overview

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

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.