Information disclosure via externally accessible files
Published May 12, 2026 · Updated May 12, 2026
Information disclosure in Microsoft Office Word allows remote attackers to expose locally accessible files after user interaction. Microsoft states that Word makes files or directories accessible to external parties, but does not identify the component, file format, or responsible operation. Exploitation requires user interaction and no privileges; the published consequence is limited to disclosure, without reported modification or interruption.
Summary
What happened
Information disclosure in Microsoft Office Word allows remote attackers to expose locally accessible files after user interaction. Microsoft states that Word makes files or directories accessible to external parties, but does not identify the component, file format, or responsible operation. Exploitation requires user interaction and no privileges; the published consequence is limited to disclosure, without reported modification or interruption.
The record
- CVE
- CVE-2026-40421
- Published
- May 12, 2026
- Updated
- May 12, 2026
- Vendor
- Microsoft
- Product
- Microsoft Office 2019
- Classifications
- CWE-73
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 12, 2026CVE publishedPublication date reported by the CVE source.
- May 12, 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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