November 14, 2026

CVE Watchtower

CVE-2026-124551classroomio classroomio Authorization Bypass Through User-Controlled Key

NVD

Vulnerability Summary

ClassroomIO through 1.0.0 contains an authorization bypass vulnerability that allows authenticated users of any organization to clone other tenants' courses via the POST /course/:courseId/clone endpoint. Attackers who know a target course id can copy its sections, lessons, exercises, and quiz answer keys into their own organization, exposing private course content.
Severity Level
MEDIUM(6.0)
Published Date
Nov 8, 2026
Last Modified
Nov 12, 2026
Exploitation Status
No confirmed exploitation yet
EPSS Score (30-Day)
0.26%Probability
Root Weakness (CWE)
CWE-639: Authorization Bypass Through User-Controlled Key ↗
The system does not prevent one user from accessing another user data or record by modifying the key value identifying the data.
CVSS v4.0 Base Metrics — Score 6.0 (MEDIUM)
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
Attack VectorNetwork
Attack ComplexityHigh
Attack RequirementsPresent
Privileges RequiredLow
User InteractionNone
Confidentiality (Vulnerable System)High
Integrity (Vulnerable System)None
Availability (Vulnerable System)None
Confidentiality (Subsequent System)None
Integrity (Subsequent System)None
Availability (Subsequent System)None
Show CVSS v3.x metrics (score 5.3)
CVSS v3.1 Base Metrics — Score 5.3 (MEDIUM)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
Attack VectorNetwork
Attack ComplexityHigh
Privileges RequiredLow
User InteractionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityNone
AvailabilityNone

Affected & Patched Versions

Affected Versions
  • classroomio classroomio <= 1.0.0
Patched Versions
  • classroomio classroomio 1.0.0

What to do

Fix it during your normal patch cycle. No exploitation is confirmed yet.

  1. Check whether you run classroomio classroomio and which version.
  2. Update to a patched version listed above, then confirm the new version.

Timeline

  • Nov 8, 2026Published
  • Nov 12, 2026Record last modified

Score, severity and exploitation changes are tracked from the day Watchtower started logging them.

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External References

Data last checked: Nov 14, 2026 02:13 UTC