CVE-2026-2345
CVE-2026-2345 is a low-severity vulnerability with a CVSS 3.x base score of 3.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-346.
Key facts
- Severity: Low (CVSS 3.x base score 3.6)
- EPSS exploit prediction: 0% (1st percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-6252
- Weakness: CWE-346
- Published:
- Last modified:
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.
Frequently asked questions
- What is CVE-2026-2345?
- 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.
- How severe is CVE-2026-2345?
- CVE-2026-2345 has a CVSS 3.x base score of 3.6, rated low severity. It is exploitable over local access with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
- Is CVE-2026-2345 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (1st percentile), an estimate of the probability of exploitation in the next 30 days.
- How do I fix CVE-2026-2345?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- Does CVE-2026-2345 have an EU (EUVD) identifier?
- Yes. CVE-2026-2345 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-6252.
- When was CVE-2026-2345 published?
- CVE-2026-2345 was published on 2026-02-11 and last updated on 2026-06-17.
References
Other CWE-346 vulnerabilities
- CVE-2026-42901 — Critical (CVSS 10.0): Origin validation error in Microsoft Entra ID allows an unauthorized attacker to elevate privileges over a network.
- CVE-2026-6508 — Critical (CVSS 9.8): Origin Validation Error vulnerability in TUBITAK BILGEM Software Technologies Research Institute Liderahenk allows…
- CVE-2026-2790 — Critical (CVSS 9.8): Same-origin policy bypass in the Networking: JAR component. This vulnerability was fixed in Firefox 148, Firefox ESR…
- CVE-2022-50925 — Critical (CVSS 9.8): Prowise Reflect version 1.0.9 contains a remote keystroke injection vulnerability that allows attackers to send…
- CVE-2025-30466 — Critical (CVSS 9.8): This issue was addressed through improved state management. This issue is fixed in Safari 18.4, iOS 18.4 and iPadOS…
- CVE-2024-8487 — Critical (CVSS 9.8): A Cross-Origin Resource Sharing (CORS) vulnerability exists in modelscope/agentscope version v0.0.4. The CORS…