CVE-2026-66318: CWE-346: Origin Validation Error in Microsoft Microsoft Edge (Chromium-based)
Origin validation error in Microsoft Edge (Chromium-based) allows an unauthorized attacker to disclose information over a network.
AI Analysis
Technical Summary
This vulnerability, tracked as CVE-2026-66318 and classified under CWE-346 (Origin Validation Error), affects Microsoft Edge (Chromium-based) version 1.0.0.0. It enables unauthorized attackers to disclose information over a network due to improper origin validation. The CVSS v3.1 base score is 8.1, indicating high severity, with attack vector network, low attack complexity, no privileges required, and user interaction required. Microsoft has released an official fix for this issue.
Potential Impact
Successful exploitation of this vulnerability can lead to unauthorized disclosure of sensitive information over a network. The integrity and availability impacts are rated high and none respectively, indicating confidentiality is primarily affected. No known exploits are reported in the wild at this time.
Mitigation Recommendations
Microsoft has provided an official fix for this vulnerability. Users and administrators should apply the security update available from Microsoft as detailed in the vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66318 to remediate this issue.
CVE-2026-66318: 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 disclose information over a network.
CVSS v3.1
Score 8.1high
Affected software
Microsoft
Microsoft Edge (Chromium-based)
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability, tracked as CVE-2026-66318 and classified under CWE-346 (Origin Validation Error), affects Microsoft Edge (Chromium-based) version 1.0.0.0. It enables unauthorized attackers to disclose information over a network due to improper origin validation. The CVSS v3.1 base score is 8.1, indicating high severity, with attack vector network, low attack complexity, no privileges required, and user interaction required. Microsoft has released an official fix for this issue.
Potential Impact
Successful exploitation of this vulnerability can lead to unauthorized disclosure of sensitive information over a network. The integrity and availability impacts are rated high and none respectively, indicating confidentiality is primarily affected. No known exploits are reported in the wild at this time.
Mitigation Recommendations
Microsoft has provided an official fix for this vulnerability. Users and administrators should apply the security update available from Microsoft as detailed in the vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66318 to remediate this issue.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-07-24T18:06:51.296Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66318","vendor":"Microsoft"}]
Threat ID: 6a7121febf32cb7a3462c086
Added to database: 08/03/2026, 23:19:26 UTC
Last enriched: 08/11/2026, 15:02:45 UTC
Last updated: 09/18/2026, 01:04:26 UTC
Views: 56
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