CVE-2026-66316: CWE-346: Origin Validation Error in Microsoft Microsoft Edge (Chromium-based)
CVE-2026-66316 is an origin validation error vulnerability in Microsoft Edge (Chromium-based) that allows an unauthorized attacker to perform spoofing over a network. The vulnerability affects version 1.0.0.0 of the product. It has a medium severity with a CVSS score of 5.4. An official fix is available from Microsoft.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-66316) involves an origin validation error in Microsoft Edge (Chromium-based) version 1.0.0.0. Due to improper validation of origin information, an attacker can spoof network communications, potentially misleading users or systems about the source of content or requests. The issue is classified under CWE-346 (Origin Validation Error). Microsoft has published an official fix for this vulnerability.
Potential Impact
The vulnerability allows an attacker to perform spoofing over a network, which could lead to limited confidentiality and integrity impacts as indicated by the CVSS vector (Confidentiality and Integrity impacts are low). There is no impact on availability. The attack requires no privileges and low attack complexity but requires user interaction. No known exploits are reported in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the patch provided by Microsoft as detailed in the vendor 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
CVE-2026-66316 is an origin validation error vulnerability in Microsoft Edge (Chromium-based) that allows an unauthorized attacker to perform spoofing over a network. The vulnerability affects version 1.0.0.0 of the product. It has a medium severity with a CVSS score of 5.4. An official fix is available from Microsoft.
CVSS v3.1
Score 5.4medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-66316) involves an origin validation error in Microsoft Edge (Chromium-based) version 1.0.0.0. Due to improper validation of origin information, an attacker can spoof network communications, potentially misleading users or systems about the source of content or requests. The issue is classified under CWE-346 (Origin Validation Error). Microsoft has published an official fix for this vulnerability.
Potential Impact
The vulnerability allows an attacker to perform spoofing over a network, which could lead to limited confidentiality and integrity impacts as indicated by the CVSS vector (Confidentiality and Integrity impacts are low). There is no impact on availability. The attack requires no privileges and low attack complexity but requires user interaction. No known exploits are reported in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the patch provided by Microsoft as detailed in the vendor 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: 08/03/2026, 23:33:54 UTC
Last updated: 08/03/2026, 23:39:07 UTC
Views: 4
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