Information disclosure via out-of-bounds read
Published Feb 10, 2026 · Updated Feb 10, 2026
Out-of-bounds read in Microsoft Office Excel allows local users to disclose information when a user opens attacker-supplied content. Microsoft has not disclosed the affected parser, buffer boundary error, or data exposed by the out-of-bounds read. Exploitation requires user interaction and provides read-only disclosure, with no reported data modification or service interruption.
Summary
What happened
Out-of-bounds read in Microsoft Office Excel allows local users to disclose information when a user opens attacker-supplied content. Microsoft has not disclosed the affected parser, buffer boundary error, or data exposed by the out-of-bounds read. Exploitation requires user interaction and provides read-only disclosure, with no reported data modification or service interruption.
The record
- CVE
- CVE-2026-21261
- Published
- Feb 10, 2026
- Updated
- Feb 10, 2026
- Vendor
- Microsoft
- Product
- Microsoft Office LTSC for Mac 2024
- Classifications
- CWE-125
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Feb 10, 2026CVE publishedPublication date reported by the CVE source.
- Feb 10, 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=16.0.0 <16.106.26020821
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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