CVE-2026-40421
MEDIUMCVSS 4.3/10EPSS 0.62%
Last modified
CVE-2026-40421 is a medium-severity vulnerability rated 4.3/10 on the CVSS scale. Files or directories accessible to external parties in Microsoft Office Word allows an unauthorized attacker to disclose information locally.. EPSS estimates a 0.62% chance of exploitation in the next 30 days.
Description
Files or directories accessible to external parties in Microsoft Office Word allows an unauthorized attacker to disclose information locally.
Metrics
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | 365 Apps | All versions |
| Microsoft | Office | 2019 |
| Microsoft | Office | 2024 |
| Microsoft | Office Long Term Servicing Channel | 2021 |
| Microsoft | Word | 2016 |
References
Timeline
- Published
- Last Modified
- Status
- Modified
Frequently Asked Questions
What is CVE-2026-40421?
Files or directories accessible to external parties in Microsoft Office Word allows an unauthorized attacker to disclose information locally.
How severe is CVE-2026-40421?
CVE-2026-40421 has a CVSS score of 4.3/10 (MEDIUM severity). The EPSS model estimates a 0.62% probability of exploitation in the next 30 days.
How do I fix CVE-2026-40421?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
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Are you affected by CVE-2026-40421?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST