Vulnerability · Published Oct 15, 2026 · Assigned by VulnCheck

CVE-2026-111369ClassroomIO through 1.0.0 Incorrect Authorization via Lesson Update and Delete Routes

High 7.1

In plain English

A high-severity incorrect authorization in ClassroomIO from classroomio. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 16% of all known vulnerabilities).

Severity (CVSS 3.1)7.1High

Exploit odds (30 days)0.2%top 84.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

ClassroomIO through 1.0.0 contains an incorrect authorization vulnerability in the PUT and DELETE /:lessonId lesson routes that allows any course member, including students, to modify lessons. Authenticated students can supply arbitrary lesson ids to change titles and stored HTML content or delete lessons in their course and in other courses and organizations.

Affected products (as reported)

Vendor	Product	Versions
classroomio	ClassroomIO	0 – through 1.0.0

Weakness: CWE-863 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L

References

https://hackmd.io/@hieuPenguinnn/classroomio-course-resource-id-scoping-idor third-party-advisory
https://github.com/classroomio/classroomio/blob/v1.0.0/apps/api/src/routes/course/lesson.ts#L107-L152 technical-description
https://github.com/classroomio/classroomio/blob/v1.0.0/apps/api/src/middlewares/course-member.ts technical-description
https://github.com/classroomio/classroomio product
VulnCheck Advisory: ClassroomIO through 1.0.0 Incorrect Authorization via Lesson Update and Delete Routes third-party-advisory