Code execution via Excel heap overflow
Published Aug 11, 2026 · Updated Aug 25, 2026
Heap-based buffer overflow in Microsoft Excel in Microsoft Office and Office Online Server allows attackers to execute code via unspecified vectors. Microsoft's CNA record and security update pages identify the flaw only as a heap overflow in Excel and do not disclose the affected parser, file format, or operation on attacker-controlled input. Exploitation requires local access and user interaction per Microsoft's CVSS vector; the public record does not describe a public exploit chain or any effect beyond code execution in the Office process context.
Summary
What happened
Heap-based buffer overflow in Microsoft Excel in Microsoft Office and Office Online Server allows attackers to execute code via unspecified vectors. Microsoft's CNA record and security update pages identify the flaw only as a heap overflow in Excel and do not disclose the affected parser, file format, or operation on attacker-controlled input. Exploitation requires local access and user interaction per Microsoft's CVSS vector; the public record does not describe a public exploit chain or any effect beyond code execution in the Office process context.
The record
- CVE
- CVE-2026-68794
- Published
- Aug 11, 2026
- Updated
- Aug 25, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-122
- 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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Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
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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