EUVD-2026-56694
GHSA-q4mx-rwhg-jjg4
Severity by source
AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Local vector and required user interaction align with document-open exploitation; PR:N reflects that any user may open a file without prior system privileges.
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 arbitrary code execution when a victim opens a specially crafted document, affecting Word 2016 through Microsoft 365 Apps and Office LTSC 2024 on both Windows and macOS. The flaw (CWE-121) scores CVSS 7.8 with high impacts across confidentiality, integrity, and availability, constrained by local attack vector and mandatory user interaction. …
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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 an affected, unpatched version of Microsoft Word - no prior authentication to the target system is required (PR:N), but user interaction is mandatory (UI:R). … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The CVSS 7.8 score reflects severe impact on all three pillars but is structurally bounded by AV:L (local execution context) and UI:R (victim must open the file), preventing direct network-triggered exploitation without a social engineering step. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | An attacker crafts a malicious Word document that triggers the stack buffer overflow in Word's document parsing component, then delivers it to the target via phishing email or a poisoned file share. When the victim opens the document in an unpatched version of Microsoft Word, the overflow overwrites the stack return address, redirecting execution to attacker-controlled shellcode running with the privileges of the logged-in user. … |
| Remediation | Apply the vendor-released patch immediately. … Detailed patch versions, workarounds, and compensating controls in full report. |
Recommended ActionAI
Within 24 hours, inventory all endpoints running Microsoft Word 2016, Microsoft 365 Apps, or Office LTSC 2024 and assess patch readiness through your endpoint management system. …
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
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External POC / Exploit Code
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