Authenticated information disclosure via Copilot Chat race
Published Aug 28, 2026 · Updated Aug 29, 2026
Race condition in Copilot Chat in Microsoft Edge before 152.0.4191.53 allows remote authenticated users to disclose information. Concurrent execution accesses a shared Copilot Chat resource without proper synchronization, but Microsoft has not identified the resource or operation. Exploitation requires authentication, network access, high-complexity timing, and user interaction; the documented consequence is limited information disclosure.
Summary
What happened
Race condition in Copilot Chat in Microsoft Edge before 152.0.4191.53 allows remote authenticated users to disclose information. Concurrent execution accesses a shared Copilot Chat resource without proper synchronization, but Microsoft has not identified the resource or operation. Exploitation requires authentication, network access, high-complexity timing, and user interaction; the documented consequence is limited information disclosure.
The record
- CVE
- CVE-2026-58616
- Published
- Aug 28, 2026
- Updated
- Aug 29, 2026
- Vendor
- Microsoft
- Product
- Microsoft Edge (Chromium-based)
- Classifications
- CWE-362
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 28, 2026CVE publishedPublication date reported by the CVE source.
- Aug 29, 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 <152.0.4191.53
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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