CVE-2026-2345: Proctorio Secure Exam Proctor Extension · Origin Validation Error
Affects Proctorio Secure Exam Proctor ExtensionSource CVE Database V5
Not known to be exploited · CVSS 3.6 Low.
Data as of 25 Oct 2026, 19:02 UTC
- EPSS
- 0.07% chance of exploitation in 30 days – higher than 0% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 11 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| ProctorioSecure Exam Proctor Extension | Affected
| Fixed in– |
AI-suggested
Organizations should monitor Proctorio vendor communications for patches addressing this vulnerability and apply updates promptly once available. Until a patch is released, users should be advised to avoid visiting untrusted websites during exam sessions to reduce the risk of malicious message injection. Security teams can audit browser extension configurations and restrict extension permissions where possible. Developers and administrators should advocate for or implement strict origin validation in all message event handlers, ensuring event.origin is checked against a whitelist of trusted domains before processing messages. Employing browser security features such as Content Security Policy (CSP) can help limit exposure to malicious scripts. User education is critical to prevent social engineering that might lead to exploitation. Finally, institutions should consider layered security controls around exam environments, including network segmentation and endpoint protection, to reduce the likelihood of local attacker presence.
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.