CVE-2026-40364
CRITICALEPSS 90th pctlDescription
Access of resource using incompatible type ('type confusion') in Microsoft Office Word allows an unauthorized attacker to execute code locally.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Exploit Intelligence
High risk: more likely to be exploited than 90% of all known CVEs.
References
Related Vulnerabilities
Other CWE-122 (Heap-based Buffer Overflow) vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2015-3113 | Critical | 9.8 | 100% | KEV | Fix |
| CVE-2024-26256 | High | 7.8 | 88% | - | Fix |
| CVE-2020-25687 | Medium | 5.9 | 87% | - | Fix |
| CVE-2009-3459 | High | 8.8 | 87% | KEV | Fix |
| CVE-2021-21017 | High | 8.8 | 86% | KEV | - |
| CVE-2020-25683 | Medium | 5.9 | 86% | - | Fix |
Common questions
How do I fix CVE-2026-40364?
Install KB5002858 for Microsoft Word 2016.
Is CVE-2026-40364 being actively exploited?
Not that we know of. CVE-2026-40364 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 4.4% is the estimated probability that it will be exploited in the next 30 days. That is higher than 90% of all scored CVEs.
How severe is CVE-2026-40364?
CVE-2026-40364 has a CVSS v3 base score of 8.4, rated critical. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
What does CVE-2026-40364 affect?
Published advisories record a fix for Microsoft Word 2016 (Microsoft). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.
Embed a live status badge for CVE-2026-40364
Markdown
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-05-19.