What is CVE-2026-78439?

CVE-2026-78439 is a security advisory published by Microsoft Security Response Center (MSRC) with Critical severity. Microsoft Office Graphics Component Remote Code Execution Vulnerability

Which CVE IDs does CVE-2026-78439 cover?

CVE-2026-78439 covers the following CVE IDs: CVE-2026-78439. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of CVE-2026-78439?

CVE-2026-78439 has a CVSS v3 base score of 8.8, published by Microsoft Security Response Center (MSRC).

Which products are affected by CVE-2026-78439?

CVE-2026-78439 affects 4 products, including: Microsoft Office 365 for Mac; Microsoft Office LTSC for Mac 2021; Microsoft Office LTSC for Mac 2024; Microsoft Office for Android.

CVE-2026-78439CriticalCVSS 8.8

Microsoft Office Graphics Component Remote Code Execution Vulnerability

Vendor

Microsoft Security Response Center (MSRC)

Published

September 11, 2026

Last Modified

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🔗 CVE IDs covered (1)

CVE-2026-78439 →

📋 Description

Stack-based buffer overflow in Microsoft Graphics Component allows an unauthorized attacker to execute code over a network.

🎯 Affected products4

Microsoft Office 365 for Mac
Microsoft Office LTSC for Mac 2021
Microsoft Office LTSC for Mac 2024
Microsoft Office for Android

✅ Remediation

KBRelease Notes (Security Update) — fixed build 16.0.20430.20000

🔗 References (3)

advisoryhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78439
patchhttps://play.google.com/store/apps/details?id=com.microsoft.office.officehubrow
referencehttps://support.google.com/googleplay/answer/113412?hl=en