Local information disclosure via out-of-bounds read
Published Sep 8, 2026 · Updated Sep 10, 2026
Out-of-bounds read in Microsoft Office Excel allows attackers to disclose information locally after required user interaction. Microsoft has not published the parser, file format, or bounds-checking operation that performs the read beyond its valid buffer. Reachability requires interaction with attacker-controlled content; the documented impact is information disclosure only.
Summary
What happened
Out-of-bounds read in Microsoft Office Excel allows attackers to disclose information locally after required user interaction. Microsoft has not published the parser, file format, or bounds-checking operation that performs the read beyond its valid buffer. Reachability requires interaction with attacker-controlled content; the documented impact is information disclosure only.
The record
- CVE
- CVE-2026-81390
- Published
- Sep 8, 2026
- Updated
- Sep 10, 2026
- Vendor
- Microsoft
- Product
- Microsoft Office LTSC for Mac 2024
- Classifications
- CWE-125, T1204
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 8, 2026CVE publishedPublication date reported by the CVE source.
- Sep 10, 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
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Technologies
Your stack
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Your stack
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