Local code execution via workbook heap overflow
Published Aug 11, 2026 · Updated Aug 25, 2026
Heap-based buffer overflow in Microsoft Office Excel on supported Office builds allows attackers to execute code locally via a crafted workbook. Microsoft has disclosed only that Excel overruns heap memory while processing untrusted workbook content; no vulnerable parser routine, file-format field, or patch diff is public as of August 19, 2026. Exploitation requires user interaction to open the malicious file, so the result is code execution in the current user's context rather than a standalone remote compromise.
Summary
What happened
Heap-based buffer overflow in Microsoft Office Excel on supported Office builds allows attackers to execute code locally via a crafted workbook. Microsoft has disclosed only that Excel overruns heap memory while processing untrusted workbook content; no vulnerable parser routine, file-format field, or patch diff is public as of August 19, 2026. Exploitation requires user interaction to open the malicious file, so the result is code execution in the current user's context rather than a standalone remote compromise.
The record
- CVE
- CVE-2026-68812
- Published
- Aug 11, 2026
- Updated
- Aug 25, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-122, T1203
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 11, 2026CVE publishedPublication date reported by the CVE source.
- Aug 25, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Affected products and versions are unavailable in this record.
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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