Heap-based buffer overflow in Microsoft Office for macOS and Microsoft Office - CVE-2026-55049
Published: July 17, 2026
Vulnerability identifier: #VU138210
CSH Severity: High
CVSS v4: 8.4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-55049
CWE-ID: CWE-122
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code.
The vulnerability exists due to heap-based buffer overflow in Microsoft Office for macOS when parsing a crafted Office file. A remote attacker can send a specially crafted file to the victim to execute arbitrary code.
User interaction is required to open the crafted file, and the Preview Pane is also an attack vector.
Affected software
Microsoft Office for macOS
Microsoft Office
Microsoft Office
How to mitigate CVE-2026-55049
Install security update from vendor's website.
Microsoft Office for macOS - update to 16.111.26071215
Microsoft Office - update to 16.0.5561.1000
Microsoft Office - update to 16.0.5561.1000