CVE-2026-78525: Microsoft Office Outlook Remote Code Execution Vulnerability
Microsoft Office Outlook Remote Code Execution Vulnerability
Other sources
Use after free in Microsoft Office Outlook allows an unauthorized attacker to execute code 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 16.0.20326.20138 - Upgrade
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Fixed in 16.0.5569.1000Patch KB5002923 - Upgrade
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Fixed in 16.0.17932.20976 - Upgrade
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Fixed in 16.0.10417.20207 - Upgrade
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Fixed in 16.0.14334.20906 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 16.113.26091433
Event History
Frequently Asked Questions
What does an attacker need to exploit this issue?
The vulnerability is remotely exploitable with low attack complexity and requires no attacker privileges. User interaction is required, so exploitation depends on a user taking an action involving attacker-controlled content.
Which deployments should be reviewed for exposure?
Review systems using Microsoft Word 2016, Microsoft 365 Apps for Enterprise, Microsoft Office 365 for Mac, Microsoft Office LTSC for Mac 2024, Microsoft Office LTSC 2024 for 32-bit or 64-bit editions, Microsoft Office 2019 for 32-bit editions, and Microsoft Office LTSC 2021 for 32-bit editions. The provided data does not identify affected configuration settings or exclusions.
What could successful exploitation allow?
Successful exploitation can allow an unauthorized attacker to execute code. The supplied severity metrics indicate high impacts to confidentiality, integrity, and availability.