CVE-2026-66317: 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 tampering over a network.
AI Analysis
Technical Summary
This vulnerability, identified as CVE-2026-66317 and classified under CWE-346 (Origin Validation Error), affects Microsoft Edge (Chromium-based). It allows an attacker to tamper with data over a network due to improper origin validation. The vulnerability is rated medium severity with a CVSS 3.1 base score of 5.4, indicating limited confidentiality and integrity impact without availability impact. Microsoft has published an official fix for this vulnerability.
Potential Impact
An attacker exploiting this vulnerability could perform tampering over a network, potentially compromising data integrity and confidentiality to a limited extent. There is no indication of availability impact or known active exploitation in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the provided security update as detailed in the Microsoft 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
Origin validation error in Microsoft Edge (Chromium-based) allows an unauthorized attacker to perform tampering over a network.
CVSS v3.1
Score 5.4medium
Affected software
Microsoft
Microsoft Edge (Chromium-based)
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability, identified as CVE-2026-66317 and classified under CWE-346 (Origin Validation Error), affects Microsoft Edge (Chromium-based). It allows an attacker to tamper with data over a network due to improper origin validation. The vulnerability is rated medium severity with a CVSS 3.1 base score of 5.4, indicating limited confidentiality and integrity impact without availability impact. Microsoft has published an official fix for this vulnerability.
Potential Impact
An attacker exploiting this vulnerability could perform tampering over a network, potentially compromising data integrity and confidentiality to a limited extent. There is no indication of availability impact or known active exploitation in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the provided security update as detailed in the Microsoft 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: 08/11/2026, 15:01:44 UTC
Last updated: 09/18/2026, 01:04:26 UTC
Views: 56
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