Code execution via heap buffer overflow
Published Aug 11, 2026 · Updated Aug 25, 2026
Heap-based buffer overflow in Microsoft Office before the August 11, 2026 security updates allows attackers to execute code locally. Microsoft has not published the affected component or the unsafe memory operation beyond classifying the flaw as a heap-based buffer overflow in the Office suite. Reachability requires local interaction with Office, and the public record does not describe a network-reachable path or privilege escalation beyond code execution.
Summary
What happened
Heap-based buffer overflow in Microsoft Office before the August 11, 2026 security updates allows attackers to execute code locally. Microsoft has not published the affected component or the unsafe memory operation beyond classifying the flaw as a heap-based buffer overflow in the Office suite. Reachability requires local interaction with Office, and the public record does not describe a network-reachable path or privilege escalation beyond code execution.
The record
- CVE
- CVE-2026-65661
- 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 conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
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.
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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