CVE-2026-97778: Microsoft Office Excel Remote Code Execution Vulnerability

Published Oct 13, 2026
·
Updated

Integer overflow or wraparound in Microsoft Office Excel allows an unauthorized attacker to execute code over a network.

Other sources

Microsoft Office Excel Remote Code Execution Vulnerability

— Microsoft

Affected Software

18 affected componentsFixes available
Microsoft Office Online Server<16.0.10417.20228
16.0.10417.20228
Microsoft Office LTSC for Mac 2021<16.114.26101123
16.114.26101123
Microsoft Office LTSC for Mac 2024<16.114.26101123
16.114.26101123
Microsoft Office 365 for Mac<16.114.26101123
16.114.26101123
Microsoft 365 Apps
Microsoft 365 Apps
Microsoft Microsoft 365 Macos
Microsoft Office 2021
Microsoft Office 2021
Microsoft Office 2021 Macos
Microsoft Office 2024
Microsoft Office 2024
Microsoft Office 2024 Macos
Microsoft Office Online Server<16.0.10417.20228
Microsoft Office LTSC 2021<16.0.14334.20974
16.0.14334.20974
Microsoft Office LTSC 2021<16.0.14334.20974
16.0.14334.20974
Microsoft Office LTSC 2024<16.0.17932.21056
16.0.17932.21056
Microsoft Office LTSC 2024<16.0.17932.21056
16.0.17932.21056

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 16.0.10417.20228Patch KB5002928
  2. Upgrade

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

    Fixed in 16.114.26101123
  3. Upgrade

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

    Fixed in 16.0.14334.20974
  4. Upgrade

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

    Fixed in 16.0.17932.21056

Event History

Oct 13, 2026
CVE Published
via Microsoft·02:00 PM
Data Sourced
via Microsoft·02:00 PM
DescriptionSeverityWeaknessAffected Software
CVE Published
via MITRE·07:00 PM
Data Sourced
via MITRE·07:00 PM
DescriptionSeverity
Data Sourced
via NVD·07:22 PM
RemedyDescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

Does exploitation require authentication or user interaction?

An attacker does not need privileges or authentication, but exploitation requires user interaction. The attack vector is network-based and has low attack complexity.

2

Which deployments should be prioritized for review?

Prioritize systems using Microsoft 365 Apps for Enterprise, Office Online Server, Office LTSC 2021 or 2024 for 32-bit or 64-bit editions, Office 365 for Mac, and Office LTSC for Mac 2021 or 2024.

3

How can I determine whether my environment is in scope?

Inventory installed Office products and compare them with the affected software list. The provided information does not identify affected build numbers, fixed versions, or detection indicators.

Contact

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