CVE-2026-78519: Microsoft Office Outlook Remote Code Execution Vulnerability
Overview
- Severity
- N/A
- Category
- Remote Code Execution
- Exploit Status
- Not Exploited
- Exploitation Likelihood
- Less Likely
- Patch Tuesday
- 2026-Sep
- Released
- 2026-09-08
Description
Use of uninitialized resource in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network.
FAQ
How could an attacker exploit the vulnerability?
In an email attack scenario, an attacker could exploit the vulnerability by sending the specially crafted email to the victim. Exploitation of the vulnerability might involve either a victim opening a specially crafted email with an affected version of Microsoft Outlook software, or a victim's Outlook application displaying a preview of a specially crafted email . This could result in the attacker executing remote code on the victim's machine.
Is the Preview Pane an attack vector for this vulnerability?
Yes, the Preview Pane is an attack vector.
Affected Products (10)
Microsoft Office
- Microsoft Office 2019 for 32-bit editions
- Microsoft Office 2019 for 64-bit editions
- Microsoft 365 Apps for Enterprise for 32-bit Systems
- Microsoft 365 Apps for Enterprise for 64-bit Systems
- Microsoft Office LTSC 2021 for 64-bit editions
- Microsoft Office LTSC 2021 for 32-bit editions
- Microsoft Office LTSC 2024 for 32-bit editions
- Microsoft Office LTSC 2024 for 64-bit editions
- Microsoft Outlook 2016 (32-bit edition)
- Microsoft Outlook 2016 (64-bit edition)
Security Updates (1)
Acknowledgments
0ccbbf129444eb66344ccafb92b00df4
Revision History
- 2026-09-08: Information published.