EUVD-2026-56709
GHSA-4hxm-v7c3-w944
Severity by source
AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Local vector and UI:R reflect file-open trigger; PR:N because no authenticated session is required to open a document; full C/I/A impact follows from arbitrary code execution.
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
Stack-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code locally.
AnalysisAI
Stack-based buffer overflow in Microsoft Office Word enables local arbitrary code execution when a user opens a maliciously crafted document. Affected products span Word 2016 through Microsoft 365 Apps for Enterprise and LTSC 2021/2024 on both Windows and macOS. …
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Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | The victim must actively open a specially crafted Word document using a vulnerable version of Microsoft Office Word on Windows or macOS. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The CVSS vector CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H scores 7.8, reflecting high-impact but user-interaction-dependent exploitation. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | An attacker crafts a malicious Word document (.docx or .doc) that contains specially structured content designed to overflow a stack buffer during the parsing phase. The document is delivered to a target via a phishing email or a compromised file-sharing link. … |
| Remediation | The primary fix is to apply Microsoft's August 2026 security update for all affected Office products. … Detailed patch versions, workarounds, and compensating controls in full report. |
Recommended ActionAI
Within 24 hours, inventory all Microsoft Office deployments to identify systems running Word 2016, 2019, Microsoft 365 Apps for Enterprise, LTSC 2021, or LTSC 2024 on Windows and macOS. …
Sign in for detailed remediation steps and compensating controls.
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Same weakness CWE-121 – Stack-based Buffer Overflow
View allSame technique Stack Overflow
View allShare
External POC / Exploit Code
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