Code execution via out-of-bounds read
Published Sep 8, 2026 · Updated Sep 9, 2026
Out-of-bounds read in Microsoft Office Excel allows remote attackers to execute code locally after a user opens a crafted file. Microsoft identifies the flaw as an out-of-bounds read in Excel but has not disclosed the affected parser, file structure, or missing bounds check. Exploitation requires user interaction and runs attacker-controlled code in the security context of the user who opens the file.
Summary
What happened
Out-of-bounds read in Microsoft Office Excel allows remote attackers to execute code locally after a user opens a crafted file. Microsoft identifies the flaw as an out-of-bounds read in Excel but has not disclosed the affected parser, file structure, or missing bounds check. Exploitation requires user interaction and runs attacker-controlled code in the security context of the user who opens the file.
The record
- CVE
- CVE-2026-81956
- Published
- Sep 8, 2026
- Updated
- Sep 9, 2026
- Vendor
- Microsoft
- Product
- Microsoft Office LTSC for Mac 2024
- Classifications
- CWE-125, T1203
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 8, 2026CVE publishedPublication date reported by the CVE source.
- Sep 9, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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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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