Summary
Impact: Remote Code Execution. Microsoft rating: Important. Not known to be exploited — Exploitation Less Likely. Customer action: Required.
Details
How could an attacker exploit this vulnerability?
An attacker with access to a user's Outlook account could submit specially crafted signature content over the network that is synchronized to the user's desktop client. Successful exploitation could allow the attacker to execute code with the user's permissions. No additional user interaction is required.
Is the Preview Pane an attack vector for this vulnerability?
No, the Preview Pane is not an attack vector.
Security updates
16.0.14334.21048 — https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates
https — https://learn.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates
Vulnerabilities 1
-
High 8.8
Microsoft Office Outlook Remote Code Execution Vulnerability
Improper limitation of a pathname to a restricted directory ('path traversal') in Microsoft Office Outlook allows an authorized attacker to execute code over a network.
Revision history
-
#1
Information published.
References
-
CVE-2026-124228 Microsoft Office Outlook Remote Code Execution Vulnerability - HTML
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-124228
-
Microsoft Exploitability Index
https://www.microsoft.com/en-us/msrc/exploitability-index?rtc=1
-
Microsoft Support Lifecycle
https://support.microsoft.com/lifecycle
-
Common Vulnerability Scoring System
https://www.first.org/cvss