CVE-2026-66317: CWE-346: Origin Validation Error in Microsoft Microsoft Edge (Chromium-based)
CVE-2026-66317 is an origin validation error vulnerability in Microsoft Edge (Chromium-based) that allows an unauthorized attacker to perform tampering over a network. 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-2026-66317) involves an origin validation error (CWE-346) in Microsoft Edge (Chromium-based). The flaw allows an attacker without privileges to tamper with data transmitted over a network. The vulnerability affects version 1.0.0.0 of Microsoft Edge (Chromium-based). Microsoft has published an official fix for this issue, and no known exploits are currently reported in the wild.
Potential Impact
An attacker can exploit the origin validation error to perform tampering over a network, potentially compromising the integrity and confidentiality of data handled by the affected browser version. The impact is limited to information disclosure and integrity loss without availability impact, rated as medium severity.
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-2026-66317 to remediate this vulnerability.
CVE-2026-66317: CWE-346: Origin Validation Error in Microsoft Microsoft Edge (Chromium-based)
Description
CVE-2026-66317 is an origin validation error vulnerability in Microsoft Edge (Chromium-based) that allows an unauthorized attacker to perform tampering over a network. 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
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-66317) involves an origin validation error (CWE-346) in Microsoft Edge (Chromium-based). The flaw allows an attacker without privileges to tamper with data transmitted over a network. The vulnerability affects version 1.0.0.0 of Microsoft Edge (Chromium-based). Microsoft has published an official fix for this issue, and no known exploits are currently reported in the wild.
Potential Impact
An attacker can exploit the origin validation error to perform tampering over a network, potentially compromising the integrity and confidentiality of data handled by the affected browser version. The impact is limited to information disclosure and integrity loss without availability impact, rated as medium severity.
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-2026-66317 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-2026-66317","vendor":"Microsoft"}]
Threat ID: 6a7121febf32cb7a3462c083
Added to database: 08/03/2026, 23:19:26 UTC
Last enriched: 08/03/2026, 23:33:48 UTC
Last updated: 08/03/2026, 23:37:52 UTC
Views: 4
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