EUVD-2026-73139
GHSA-m79q-5fg4-88gp
Severity by source
AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Document delivered over network with no attacker privileges; user must open the file (UI:R); heap overflow yields full C/I/A impact with low complexity once triggered.
Primary rating from Vendor (microsoft).
CVSS VectorVendor: microsoft
Lifecycle Timeline
4DescriptionCVE.org
Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code over a network.
AnalysisAI
Heap-based buffer overflow (CWE-122) in Microsoft Office Word enables unauthenticated remote code execution when a victim opens a specially crafted document. All currently supported Office product lines are affected across Windows (x86/x64) and macOS, including Microsoft 365 Apps for Enterprise, Office 2016, 2019, 2021 LTSC, 2024 LTSC, and Microsoft 365 for Mac. …
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Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | A victim must actively open a specially crafted Word document - user interaction is required (UI:R per CVSS vector). … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | CVSS 8.8 (AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) accurately reflects the threat model: network-deliverable, low complexity, no attacker privileges required, and full C/I/A impact upon successful exploitation. … 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 security updates for all affected Office product lines. … Detailed patch versions, workarounds, and compensating controls in full report. |
Recommended ActionAI
Within 24 hours: Inventory all Microsoft Office deployments (Office 2016, 2019, 2021 LTSC, 2024 LTSC, Microsoft 365 Apps for Enterprise, Microsoft 365 for Mac) across Windows and macOS to identify affected systems; disable external email document previews and restrict opening Office documents from untrusted sources as interim protection. …
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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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