Unauthenticated network information disclosure
Published Aug 3, 2026 · Updated Aug 3, 2026
Origin validation error in Microsoft Edge before 151.0.4129.59 allows remote attackers to disclose information through network content. Microsoft has not published the affected component or the validation operation that mishandles an untrusted origin. Exploitation requires no account but does require user interaction; Microsoft has not identified the exposed information or an availability consequence.
Summary
What happened
Origin validation error in Microsoft Edge before 151.0.4129.59 allows remote attackers to disclose information through network content. Microsoft has not published the affected component or the validation operation that mishandles an untrusted origin. Exploitation requires no account but does require user interaction; Microsoft has not identified the exposed information or an availability consequence.
The record
- CVE
- CVE-2026-66318
- Published
- Aug 3, 2026
- Updated
- Aug 3, 2026
- Vendor
- Microsoft
- Product
- Microsoft Edge (Chromium-based)
- Classifications
- CWE-346
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 3, 2026CVE publishedPublication date reported by the CVE source.
- Aug 3, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=1.0.0.0 <151.0.4129.59
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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