Code execution via heap buffer overflow
Published Jul 14, 2026 · Updated Jul 14, 2026
Heap-based buffer overflow in Microsoft Office Word allows attackers to execute code through a crafted document opened locally by a user. Microsoft identifies the affected component only as Office Word and has not published the faulty parser, memory-copy operation, or input structure that overruns the heap. Exploitation requires user interaction, after which code runs with that user's privileges and can access or alter data available to the Word process.
Summary
What happened
Heap-based buffer overflow in Microsoft Office Word allows attackers to execute code through a crafted document opened locally by a user. Microsoft identifies the affected component only as Office Word and has not published the faulty parser, memory-copy operation, or input structure that overruns the heap. Exploitation requires user interaction, after which code runs with that user's privileges and can access or alter data available to the Word process.
The record
- CVE
- CVE-2026-55130
- Published
- Jul 14, 2026
- Updated
- Jul 14, 2026
- Vendor
- Microsoft
- Product
- Microsoft Office 2019
- Classifications
- CWE-787, CWE-122, T1203, T1204.002
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 14, 2026CVE publishedPublication date reported by the CVE source.
- Jul 14, 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=19.0.0 <https://aka.ms/OfficeSecurityReleases
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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