EUVD-2026-73308
GHSA-mp8c-hc24-4rfr
Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Network delivery of a malicious document, but exploitation realistically needs the victim to open/preview it (UI:R rather than the vendor's UI:N); full RCE gives C:H/I:H/A:H.
Primary rating from Vendor (microsoft).
CVSS VectorVendor: microsoft
Lifecycle Timeline
3DescriptionCVE.org
Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code over a network.
AnalysisAI
Remote code execution in Microsoft Office Word arises from a heap-based buffer overflow (CWE-122) that a remote attacker can trigger to run arbitrary code with the victim's privileges. It affects a broad set of Office builds including Microsoft 365 Apps for Enterprise, Office LTSC 2021/2024, Office 2016/2019, and the macOS Office editions. …
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Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | Exploitation requires the victim to receive and process a crafted Word document in a vulnerable Office build (Microsoft 365 Apps, Office LTSC 2021/2024, Office 2016/2019, or the listed Mac editions). … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The vendor CVSS 3.1 vector (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H, 9.8) describes a network, low-complexity, unauthenticated attack requiring no user interaction and yielding full confidentiality, integrity, and availability impact - a worst-case profile. … 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 update for your Office channel per the MSRC advisory (https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78510): Patch available per vendor advisory, with fixed builds of 16.0.20326.20136 for Microsoft 365 Apps for Enterprise, 16.0.14334.20896 for Office LTSC 2021, 16.0.17932.20960 for Office LTSC 2024, 16.0.5569.1000 for Office 2016, and 16.0.10417.20204 for Office 2019; macOS editions should be updated to the latest Microsoft AutoUpdate build. … Detailed patch versions, workarounds, and compensating controls in full report. |
Recommended ActionAI
Within 24 hours, identify the specific patch version for each affected Office product line (Office 365 Apps for Enterprise, Office LTSC 2021, Office LTSC 2024, Office 2016, Office 2019, and macOS editions) and begin user communication about not opening untrusted attachments. …
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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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