EUVD-2026-73304
GHSA-fxpv-5g5v-9223
Severity by source
AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Network-delivered document, no auth or configuration prerequisites; user must open file (UI:R); full code execution yields C:H/I:H/A:H with no scope change.
Primary rating from Vendor (microsoft).
CVSS VectorVendor: microsoft
Lifecycle Timeline
3DescriptionCVE.org
Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code over a network.
AnalysisAI
Remote code execution in Microsoft Office Word exposes virtually every Windows and macOS Office release channel - Word 2016, Office 2019, LTSC 2021/2024, 365 Apps for Enterprise, and Office for Mac - to full system compromise via a specially crafted document. The heap-based buffer overflow (CWE-122) fires during document parsing with no authentication required from the attacker, only standard user interaction to open the malicious file, yielding C:H/I:H/A:H impact under a low-complexity attack path. …
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Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | The victim must open a specially crafted Word document; delivery can occur via any file-transfer channel - phishing email attachment, browser download from a web link, SMB share, or cloud storage link. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The CVSS 8.8 base score accurately reflects a high-priority patching target: no authentication or elevated privileges are required from the attacker's side, attack complexity is low, and the only barrier is persuading a victim to open a document - a well-operationalized social-engineering step in phishing campaigns. … 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 Microsoft's patches immediately via Microsoft Update or the Microsoft Update Catalog for each affected Windows channel: upgrade Word 2016 to build 16.0.5569.1000 or later, Office 2019 to 16.0.10417.20204 or later, Office LTSC 2021 to 16.0.14334.20896 or later, Office LTSC 2024 to 16.0.17932.20960 or later, and Microsoft 365 Apps for Enterprise to 16.0.20326.20136 or later. … Detailed patch versions, workarounds, and compensating controls in full report. |
Recommended ActionAI
Within 24 hours, conduct a comprehensive audit of Microsoft Office installations across all Windows and macOS systems (Word 2016, Office 2019, LTSC 2021, LTSC 2024, 365 Apps for Enterprise, Office for Mac); issue security guidance advising users to avoid opening unsolicited documents and coordinate with IT operations to prepare patch deployment. …
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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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