EUVD-2026-73865
GHSA-4f9x-mwh2-mfqr
Severity by source
AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
File-based local execution (AV:L), no system privileges needed (PR:N), user must open document (UI:R), full triad impact with no scope change.
Primary rating from Vendor (microsoft).
CVSS VectorVendor: microsoft
Lifecycle Timeline
3DescriptionCVE.org
Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
AnalysisAI
Heap-based buffer overflow in Microsoft Office Excel enables local code execution when a user opens a specially crafted workbook. The vulnerability (CWE-122) affects all major Office perpetual and subscription editions across Windows and Mac, spanning Excel 2016 through Microsoft 365 Apps for Enterprise. …
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Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | The victim must open a specially crafted Excel workbook file on an affected system - no network listener or pre-existing access to the target machine is required by the attacker beyond file delivery. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The provided CVSS 7.8 (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) accurately reflects the threat model: low complexity, no prior privileges on the system, but requires user interaction to open a malicious file. … 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 patch via Windows Update or Microsoft Update Catalog - specific fix builds are 16.0.5569.1003 for Office/Excel 2016, 16.0.10417.20204 for Office 2019, 16.0.14334.20896 for Office LTSC 2021, 16.0.17932.20960 for Office LTSC 2024, and 16.0.20131.20246 for Microsoft 365 Apps for Enterprise. … Detailed patch versions, workarounds, and compensating controls in full report. |
Recommended ActionAI
Within 24 hours, identify and catalog all Microsoft Excel installations across the organization, including both perpetual licenses (Excel 2016, 2019) and subscription deployments (Microsoft 365 Apps for Enterprise) on Windows and macOS endpoints. …
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Threat intelligence, references, and detailed analysis are available after sign-in.
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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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