EUVD-2026-56717
GHSA-7r87-rqc6-m6vh
Severity by source
AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Local file-based attack with mandatory user interaction and no privilege requirement; full C/I/A impact reflects arbitrary code execution in user context.
Primary rating from Vendor (microsoft).
CVSS VectorVendor: microsoft
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Lifecycle Timeline
3DescriptionCVE.org
Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code locally.
AnalysisAI
Heap-based buffer overflow in Microsoft Office Word enables local code execution with High confidentiality, integrity, and availability impact when a user opens a specially crafted document. Affects Microsoft Office 2019, Microsoft 365 Apps for Enterprise, Office LTSC 2021 and 2024, Word 2016, and corresponding Mac editions. …
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Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | The attacker must deliver a specially crafted Word document to the target and the target user must actively open the document in a vulnerable version of Microsoft Word - this is the UI:R requirement reflected in the CVSS vector. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | CVSS 7.8 High with vector AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H reflects a serious but user-interaction-dependent local code execution flaw. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | An attacker sends a crafted Word document to a target employee via phishing email. When the recipient opens the attachment in an unpatched version of Microsoft Word, the document parser triggers the heap-based buffer overflow, overwriting adjacent heap memory structures and redirecting execution to attacker-controlled shellcode. … |
| Remediation | Primary remediation is to apply the vendor-released patch immediately via Microsoft Update or Microsoft 365 Admin Center. … Detailed patch versions, workarounds, and compensating controls in full report. |
Recommended ActionAI
Within 24 hours, confirm patch availability from Microsoft Security Advisories and inventory all affected Office versions in your enterprise to establish a deployment roadmap by business criticality and user roles. …
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Same weakness CWE-122 – Heap-based Buffer Overflow
View allSame technique Heap Overflow
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External POC / Exploit Code
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