Out-of-bounds read in Microsoft Office for macOS and Microsoft Office - CVE-2026-63515

Vulnerability details

The vulnerability allows a remote attacker to execute arbitrary code.

The vulnerability exists due to out-of-bounds read in Microsoft Office when parsing a crafted Office file. A remote attacker can send a specially crafted file to a user to execute arbitrary code.

The Preview Pane is an attack vector, and user interaction is required to open or preview the crafted file.

Affected software

How to mitigate CVE-2026-63515

External References

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2026-63515
• https://www.microsoft.com/en-us/microsoft-365/mac/microsoft-365-for-mac?msockid=35f9adb0e74b61392038b90de6fe608c

Related Security Bulletins

• Multiple vulnerabilities in Microsoft Office