CVE-2026-66313: CWE-346: Origin Validation Error in Microsoft Microsoft Edge (Chromium-based)
CVE-2026-66313 is an origin validation error vulnerability in Microsoft Edge (Chromium-based) that allows an unauthorized attacker to perform local tampering. It affects version 1.0.0.0 of the product. The vulnerability has a medium severity with a CVSS score of 6.8. An official fix is available from Microsoft.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-66313) involves an origin validation error in Microsoft Edge (Chromium-based) version 1.0.0.0. The flaw allows an unauthorized attacker to perform tampering locally, potentially compromising confidentiality with limited integrity impact and no availability impact. The CVSS vector indicates low attack complexity, no privileges required, and no user interaction needed. Microsoft has published an official fix for this vulnerability.
Potential Impact
An attacker with local access can exploit this origin validation error to tamper with the application, leading to a high confidentiality impact and limited integrity impact. There is no impact on availability. The vulnerability does not require privileges or user interaction to exploit, but local access is necessary.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the vendor-provided patch as detailed in the Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66313 to remediate this vulnerability.
CVE-2026-66313: CWE-346: Origin Validation Error in Microsoft Microsoft Edge (Chromium-based)
Description
CVE-2026-66313 is an origin validation error vulnerability in Microsoft Edge (Chromium-based) that allows an unauthorized attacker to perform local tampering. It affects version 1.0.0.0 of the product. The vulnerability has a medium severity with a CVSS score of 6.8. An official fix is available from Microsoft.
CVSS v3.1
Score 6.8medium
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-66313) involves an origin validation error in Microsoft Edge (Chromium-based) version 1.0.0.0. The flaw allows an unauthorized attacker to perform tampering locally, potentially compromising confidentiality with limited integrity impact and no availability impact. The CVSS vector indicates low attack complexity, no privileges required, and no user interaction needed. Microsoft has published an official fix for this vulnerability.
Potential Impact
An attacker with local access can exploit this origin validation error to tamper with the application, leading to a high confidentiality impact and limited integrity impact. There is no impact on availability. The vulnerability does not require privileges or user interaction to exploit, but local access is necessary.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the vendor-provided patch as detailed in the Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66313 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-2026-66313","vendor":"Microsoft"}]
Threat ID: 6a7121fcbf32cb7a3462c05e
Added to database: 08/03/2026, 23:19:24 UTC
Last enriched: 08/03/2026, 23:34:06 UTC
Last updated: 08/04/2026, 02:09:54 UTC
Views: 5
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