CVE-2026-78503: Microsoft Office Word Information Disclosure Vulnerability
Microsoft Office Word Information Disclosure Vulnerability
Other sources
Out-of-bounds read in Microsoft Office Word allows an unauthorized attacker to disclose information over a network.
— 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 16.0.17932.20976 - 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 16.0.14334.20906 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 16.0.20326.20138 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 16.0.10417.20207
Event History
Frequently Asked Questions
Which Office deployments are listed as affected?
The affected software list includes Word 2016, Microsoft 365 Apps for Enterprise, Office 365 for Mac, Office LTSC for Mac 2021 and 2024, Office LTSC 2021 for 32-bit editions, and Office LTSC 2024 for 32-bit and 64-bit editions.
Does exploitation require prior authentication or elevated privileges?
No privileges are required according to the supplied vector (PR:N). The attack is network-based and has low attack complexity, but it requires user interaction.
What is the expected impact if exploitation succeeds?
Successful exploitation can disclose information. The provided impact ratings indicate high confidentiality impact and no integrity or availability impact.