CVE-2026-78517: Microsoft Office Word Remote Code Execution Vulnerability
Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code over a network.
Other sources
Microsoft Office Word Remote Code Execution Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 16.0.5569.1000Patch KB5002923 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 16.0.17932.20960 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 16.0.14334.20896 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 16.0.20326.20136 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 16.0.10417.20204
Event History
Frequently Asked Questions
What does an attacker need to exploit this issue?
The attacker does not need privileges and can target the vulnerability over a network, but exploitation requires user interaction.
Which deployments should be checked for exposure?
Check Microsoft Word 2016, Microsoft 365 Apps for Enterprise, Microsoft Office Word, Office LTSC 2021 for 32-bit and 64-bit editions, Office LTSC 2024 for 32-bit and 64-bit editions, and Office LTSC for Mac 2024.
Are Mac systems included in the affected software list?
Yes. Microsoft Office LTSC for Mac 2024 is listed as affected.