Heap-based buffer overflow in Microsoft Office - CVE-2026-108426
Published: November 5, 2026
Vulnerability identifier: #VU159346
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-2026-108426
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 on the affected system.
The vulnerability exists due to a heap-based buffer overflow in Microsoft Office Word when processing a specially crafted file. A remote attacker can trick a user into opening the file to execute arbitrary code on the affected system.
The Preview Pane is not an attack vector for this vulnerability.
Affected software
Microsoft Office
How to mitigate CVE-2026-108426
Install security update from vendor's website.
Microsoft Office - addressed in versions 16.0.14334.20974, 16.0.17932.21056