CVE-2026-2345

Insufficient Origin Validation in Proctorio Chrome Extension postMessage Handlers

Published Feb 11, 2026 CVSS 3.1 · 3.6 Low EPSS < 1% KEV · Not listed
Description
Proctorio Chrome Extension is a browser extension used for online proctoring. The extension contains multiple window.addEventListener('message', ...) handlers that do not properly validate the origin of incoming messages. Specifically, an internal messaging bridge processes messages based solely on the presence of a fromWebsite property without verifying the event.origin attribute.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Proctorio
Proctorio secure Exam Proctor Extension
Vendors & Products Proctorio
Proctorio secure Exam Proctor Extension
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Proctorio Chrome Extension is a browser extension used for online proctoring. The extension contains multiple window.addEventListener('message', ...) handlers that do not properly validate the origin of incoming messages. Specifically, an internal messaging bridge processes messages based solely on the presence of a fromWebsite property without verifying the event.origin attribute.
Title Insufficient Origin Validation in Proctorio Chrome Extension postMessage Handlers
Weaknesses CWE-346
References
Metrics cvssV3_1

{'score': 3.6, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
Hackrate
Published
Updated
Feb 11, 2026, 9:19 PM
Reserved
Feb 11, 2026, 2:45 PM
Status
Deferred
Published
Feb 11, 2026, 3:16 PM
Modified
Jun 17, 2026, 10:30 AM