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CVE-2026-78439

High

Description

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

SeverityHigh
CVSS8.8
Exploit probability—
ProductMicrosoft Office 365 for Mac
PublishedSep 8, 2026
First seenSep 8, 2026
Weakness typeCWE-121CWE-121

How to fix

Update
  • Microsoft Microsoft Office 365 for Mac16.113.26091433 or later
  • Microsoft Microsoft Office for Android16.0.20430.20000 or later
  • Microsoft Microsoft Office LTSC for Mac 202116.113.26091433 or later
  • Microsoft Microsoft Office LTSC for Mac 202416.113.26091433 or later
Patches

Affected products

ProductAffected versionsFixed in
Microsoft Microsoft Office 365 for Mac1.0.0 ≤ v < 16.113.2609143316.113.26091433
Microsoft Microsoft Office for Android16.0.1 ≤ v < 16.0.20430.2000016.0.20430.20000
Microsoft Microsoft Office LTSC for Mac 202116.0.1 ≤ v < 16.113.2609143316.113.26091433
Microsoft Microsoft Office LTSC for Mac 202416.0.0 ≤ v < 16.113.2609143316.113.26091433

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