Unauthenticated remote code execution
Published Jul 23, 2026 · Updated Jul 24, 2026
Heap-based buffer overflow in Microsoft account allows remote attackers to execute code through the hosted identity service. Microsoft has not disclosed the affected service component, the input that reaches the heap buffer, or the out-of-bounds write operation. Exploitation requires no authentication or user interaction and grants code execution in the service security context.
Summary
What happened
Heap-based buffer overflow in Microsoft account allows remote attackers to execute code through the hosted identity service. Microsoft has not disclosed the affected service component, the input that reaches the heap buffer, or the out-of-bounds write operation. Exploitation requires no authentication or user interaction and grants code execution in the service security context.
The record
- CVE
- CVE-2026-56165
- Published
- Jul 23, 2026
- Updated
- Jul 24, 2026
- Vendor
- Microsoft
- Product
- Microsoft account
- Classifications
- CWE-122, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 23, 2026CVE publishedPublication date reported by the CVE source.
- Jul 24, 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?
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- Affected versionversion=-
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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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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