CVE-2026-66316: CWE-346: Origin Validation Error in Microsoft Microsoft Edge (Chromium-based)
Origin validation error in Microsoft Edge (Chromium-based) allows an unauthorized attacker to perform spoofing over a network.
AI Analysis
Technical Summary
This vulnerability, identified as CWE-346 (Origin Validation Error), affects Microsoft Edge (Chromium-based) version 1.0.0.0. It allows an attacker to spoof network communications by exploiting improper origin validation. The issue has been officially fixed by Microsoft, and a patch is available as detailed in the Microsoft Security Response Center advisory.
Potential Impact
Exploitation of this vulnerability can lead to spoofing attacks over a network, potentially allowing an attacker to impersonate trusted origins. The impact is limited to confidentiality and integrity with no reported impact on availability. The CVSS score of 5.4 reflects a medium severity level.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66316 to remediate this vulnerability.
CVE-2026-66316: CWE-346: Origin Validation Error in Microsoft Microsoft Edge (Chromium-based)
Description
Origin validation error in Microsoft Edge (Chromium-based) allows an unauthorized attacker to perform spoofing over a network.
CVSS v3.1
Score 5.4medium
Affected software
Microsoft
Microsoft Edge (Chromium-based)
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability, identified as CWE-346 (Origin Validation Error), affects Microsoft Edge (Chromium-based) version 1.0.0.0. It allows an attacker to spoof network communications by exploiting improper origin validation. The issue has been officially fixed by Microsoft, and a patch is available as detailed in the Microsoft Security Response Center advisory.
Potential Impact
Exploitation of this vulnerability can lead to spoofing attacks over a network, potentially allowing an attacker to impersonate trusted origins. The impact is limited to confidentiality and integrity with no reported impact on availability. The CVSS score of 5.4 reflects a medium severity level.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66316 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-07-24T18:06:51.295Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66316","vendor":"Microsoft"}]
Threat ID: 6a7121febf32cb7a3462c080
Added to database: 08/03/2026, 23:19:26 UTC
Last enriched: 08/11/2026, 15:00:50 UTC
Last updated: 09/18/2026, 01:04:25 UTC
Views: 49
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