Main Vulnerability Database Vulnerabilities #VU138244

Heap-based buffer overflow in Microsoft Office for macOS and Microsoft PowerPoint - CVE-2026-55123

Published: July 17, 2026

Vulnerability identifier: #VU138244

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-2026-55123

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 PowerPoint when parsing a crafted Office file. A remote attacker can send a specially crafted file to execute arbitrary code.

User interaction is required to open the crafted file, and the Preview Pane is not an attack vector.

Affected software

Microsoft Office for macOS
Microsoft PowerPoint

How to mitigate CVE-2026-55123

Install security update from vendor's website.

Microsoft Office for macOS - update to 16.111.26071215
Microsoft PowerPoint - update to 16.0.5561.1000

External References

Related Security Bulletins