Code execution via undisclosed integer underflow
Published Jul 11, 2023 · Updated Feb 28, 2025
Integer underflow in Microsoft Excel allows attackers to execute code when a user opens a crafted workbook in an affected Office product. Microsoft identifies CWE-191 but has not published the parser, file structure, or arithmetic operation that underflows while processing workbook input. Exploitation requires user interaction; successful execution runs in the user's security context and can read, change, or delete data available to that user.
Summary
What happened
Integer underflow in Microsoft Excel allows attackers to execute code when a user opens a crafted workbook in an affected Office product. Microsoft identifies CWE-191 but has not published the parser, file structure, or arithmetic operation that underflows while processing workbook input. Exploitation requires user interaction; successful execution runs in the user's security context and can read, change, or delete data available to that user.
The record
- CVE
- CVE-2023-33158
- Published
- Jul 11, 2023
- Updated
- Feb 28, 2025
- Vendor
- Microsoft
- Product
- Microsoft Office LTSC for Mac 2021
- Classifications
- CWE-191, T1204.002
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 11, 2023CVE publishedPublication date reported by the CVE source.
- Feb 28, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=16.0.1 <16.75.23070901
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
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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