Code execution via malicious document processing
Published Jul 16, 2021 · Updated Aug 10, 2026
Remote code execution in Microsoft Word for Office 2019, Word 2016, and Microsoft 365 Apps allows attackers to run code through a document. Microsoft has not disclosed the affected parser, object type, or incorrect memory operation performed while processing document content. Exploitation requires a user to open attacker-controlled content, and resulting code executes in that user's security context.
Summary
What happened
Remote code execution in Microsoft Word for Office 2019, Word 2016, and Microsoft 365 Apps allows attackers to run code through a document. Microsoft has not disclosed the affected parser, object type, or incorrect memory operation performed while processing document content. Exploitation requires a user to open attacker-controlled content, and resulting code executes in that user's security context.
The record
- CVE
- CVE-2021-34452
- Published
- Jul 16, 2021
- Updated
- Aug 10, 2026
- Vendor
- Microsoft
- Product
- Microsoft Office 2019
- Classifications
- T1204.002, T1566.001
- Attack vector
- Unavailable
- Privileges
- Unavailable
Timeline
How it unfolded
- Jul 16, 2021CVE publishedPublication date reported by the CVE source.
- Aug 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=19.0.0 <https://aka.ms/OfficeSecurityReleases
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
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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