---
id: CVE-2026-111368
title: >-
  ClassroomIO through 1.0.0 IDOR via Course Submission Update, Grade and Delete
  Routes
summary: >-
  ClassroomIO through 1.0.0 contains an insecure direct object reference
  vulnerability in the Hono API course submission routes that allows course
  tutors or admins to modify submissions in other courses. Attackers can supply
  their own cour…
severity: medium
cvss: 6.4
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:L'
cvssSource: cna
cwe:
  - CWE-639
vendor: classroomio
product: ClassroomIO
affected:
  - ClassroomIO <= 1.0.0
published: '2026-10-15'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T21:43:51.616Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-111368'
references:
  - url: >-
      https://hackmd.io/@hieuPenguinnn/classroomio-course-resource-id-scoping-idor
  - url: >-
      https://github.com/classroomio/classroomio/blob/v1.0.0/apps/api/src/routes/course/submission.ts
  - url: >-
      https://github.com/classroomio/classroomio/blob/v1.0.0/packages/db/src/queries/submission/submission.ts#L217-L245
  - url: >-
      https://github.com/classroomio/classroomio/commit/1844ad9671a0d9c2566d3431d82f34d39016242c
  - url: 'https://github.com/classroomio/classroomio'
  - url: >-
      https://www.vulncheck.com/advisories/classroomio-through-1.0.0-idor-via-course-submission-update-grade-and-delete-routes
    label: >-
      VulnCheck Advisory: ClassroomIO through 1.0.0 IDOR via Course Submission
      Update, Grade and Delete Routes
tags:
  - cve.org
ingestedAt: '2026-10-15T22:48:25.460Z'
---

## Overview

ClassroomIO through 1.0.0 contains an insecure direct object reference vulnerability in the Hono API course submission routes that allows course tutors or admins to modify submissions in other courses. Attackers can supply their own course id with another course's submission UUID to PUT or DELETE handlers to overwrite answers, grades, feedback, and grading status or delete submissions.

## Affected

- `ClassroomIO <= 1.0.0`

## Remediation

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