CVE-2026-2345
Insufficient Origin Validation in Proctorio Chrome Extension postMessage Handlers
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.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- High
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Insufficient Origin Validation in Proctorio Chrome Extension postMessage Handlers
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.
- Record
CVE-2026-2345- CVSS 3.1
- 3.6 Low
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N - Weakness
- CWE-346
- Updated
- 2026-11-02
EUVDEUVD-2026-6252
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.
- Record
EUVD-2026-6252- CVSS 3.1
- 3.6 Low
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-f688-gwj3-8h54
Proctorio Chrome Extension is a browser extension used for online proctoring. The extension...
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.
- Record
GHSA-f688-gwj3-8h54- CVSS 3.1
- 3.6 Low
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N - Weakness
- CWE-346
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-2345- CVSS 3.1
- 3.6 Low
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N - Weakness
- CWE-346
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-2345 is a low vulnerability (CVSS 3.6) in Proctorio Secure Exam Proctor Extension, published February 11, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.08%, the 0th percentile. No source names a fixed version.