EUVD-2026-73818
GHSA-wmm4-h5xq-67rx
Severity by source
AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Network-delivered document exploit requiring no authentication; user must open file (UI:R); successful heap overflow yields full code execution (C:H/I:H/A:H).
Primary rating from Vendor (microsoft).
CVSS VectorVendor: microsoft
Lifecycle Timeline
3DescriptionCVE.org
Numeric truncation error in Microsoft Office Word allows an unauthorized attacker to execute code over a network.
AnalysisAI
Heap-based buffer overflow in Microsoft Word's document-parsing engine, arising from a numeric truncation error, enables remote code execution when a user opens a specially crafted Word document. The flaw spans a wide matrix of Office SKUs on both Windows and Mac - including Office 2016, 2019, LTSC 2021/2024, Microsoft 365 Apps for Enterprise, and Mac variants - and carries CVSS 8.8 (AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H), reflecting full compromise with the only friction being the required user interaction. …
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Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | The victim must open a specially crafted Microsoft Word document, providing the required user interaction (UI:R). … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The CVSS 8.8 vector (AV:N/AC:L/PR:N/UI:R) accurately characterises the threat: a malicious Word document delivered via email or web download can compromise any unpatched host the moment a user opens it, requiring no authentication and no special server-side configuration. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | Full exploit scenario with step-by-step reproduction available after sign-in. |
| Remediation | Apply the Microsoft-released security update through Windows Update, Microsoft Update Catalog, or enterprise patch management tooling. … Detailed patch versions, workarounds, and compensating controls in full report. |
Recommended ActionAI
Within 24 hours, inventory all systems running Microsoft Office 2016, 2019, LTSC 2021/2024, or Microsoft 365 Apps for Enterprise on Windows and macOS to establish baseline exposure. …
Sign in for detailed remediation steps and compensating controls.
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Same weakness CWE-122 – Heap-based Buffer Overflow
View allSame technique Buffer Overflow
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External POC / Exploit Code
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