CVE-2026-78510: Microsoft Word Remote Code Execution Vulnerability

Published Sep 8, 2026
·
Updated

Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code over a network.

Other sources

Microsoft Word Remote Code Execution Vulnerability

Microsoft

Affected Software

13 affected componentsFixes available
Microsoft Office 2016<16.0.5569.1000
16.0.5569.1000
Microsoft Office LTSC 2024 for 64-bit editions<16.0.17932.20960
16.0.17932.20960
Microsoft Office 2016<16.0.5569.1000
16.0.5569.1000
Microsoft Office 365 for Mac
Microsoft 365 Apps for Enterprise<16.0.20326.20136
16.0.20326.20136
Microsoft Office LTSC 2021 for 64-bit editions<16.0.14334.20896
16.0.14334.20896
Microsoft Office LTSC 2024 for 32-bit editions<16.0.17932.20960
16.0.17932.20960
Microsoft Office LTSC 2021 for 32-bit editions<16.0.14334.20896
16.0.14334.20896
Microsoft Office LTSC for Mac 2024
Microsoft 365 Apps for Enterprise<16.0.20326.20136
16.0.20326.20136
Microsoft Office LTSC for Mac 2021
Microsoft Office 2019 for 64-bit editions<16.0.10417.20204
16.0.10417.20204
Microsoft Office 2019 for 32-bit editions<16.0.10417.20204
16.0.10417.20204

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 16.0.5569.1000Patch KB5002916
  2. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 16.0.17932.20960
  3. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 16.0.14334.20896
  4. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 16.0.20326.20136
  5. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 16.0.10417.20204

Event History

Sep 8, 2026
CVE Published
via Microsoft·02:00 PM
Data Sourced
via Microsoft·02:00 PM
DescriptionSeverityWeaknessAffected Software
Updated
via Microsoft·02:00 PM
SeverityAffected Software
Updated
via Microsoft·02:00 PM
Affected Software
Updated
via Microsoft·02:00 PM
Description
CVE Published
via MITRE·05:13 PM
Data Sourced
via MITRE·05:13 PM
DescriptionSeverity

Frequently Asked Questions

1

Which Microsoft Office deployments should be treated as potentially affected?

The affected software list includes Microsoft Office 2016; Microsoft 365 Apps for Enterprise; Office LTSC 2021 and 2024 in both 32-bit and 64-bit editions; Office 365 for Mac; and Office LTSC for Mac 2024.

2

Does exploitation require authentication, elevated privileges, or user interaction?

The supplied CVSS vector indicates network attackability with low attack complexity and no required privileges or user interaction. The description also identifies the attacker as unauthorized.

3

Does the provided information identify a specific fixed version or workaround?

No fixed build, update package, workaround, or mitigation is provided in the available data. The listed Microsoft reference is the only remediation-related source supplied.

Contact

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