Microsoft Security Response CenterCVE-2026-78439

Microsoft Office Graphics Component Remote Code Execution Vulnerability

CriticalVendor CVSS 8.8 / 10 1 CVE Published Sep 8, 2026 at 7:00 AM UTC

Summary

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

Release Notes

Update history

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Sep 8, 2026 at 7:00 AM UTC
Published by Microsoft Security Response Center
The publication date reported by the vendor.
Sep 8, 2026 at 7:15 PM UTC
Added to SecurityAlert
We collected the advisory from the official source.
Sep 17, 2026 at 7:00 AM UTC
Updated by Microsoft Security Response Center
The vendor changed the advisory after it was first published.
Oct 28, 2026 at 3:45 AM UTC
Confirmed at the source
Our collector saw this advisory during a later source check.

Details collected from Microsoft Security Response Center.

Official bulletin How SecurityAlert builds this record

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