Local code execution via heap overflow
Published Aug 11, 2026 · Updated Aug 25, 2026
Heap-based buffer overflow in Microsoft Office Excel in Microsoft Office before August 2026 updates allows attackers to execute code locally. Microsoft has not disclosed the affected parser, workbook record, or exact memory operation beyond classifying the flaw as a heap-based buffer overflow in Excel. Reachability is client-side: public scoring requires user interaction and no attacker privileges, so exposure depends on opening attacker-controlled Excel content, and inspected records did not report public exploitation.
Summary
What happened
Heap-based buffer overflow in Microsoft Office Excel in Microsoft Office before August 2026 updates allows attackers to execute code locally. Microsoft has not disclosed the affected parser, workbook record, or exact memory operation beyond classifying the flaw as a heap-based buffer overflow in Excel. Reachability is client-side: public scoring requires user interaction and no attacker privileges, so exposure depends on opening attacker-controlled Excel content, and inspected records did not report public exploitation.
The record
- CVE
- CVE-2026-68800
- Published
- Aug 11, 2026
- Updated
- Aug 25, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-122, T1203
- 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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What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
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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.
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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