Use-after-free in Microsoft products - CVE-2026-45458

Vulnerability identifier: #VU134244

CSH Severity: High

CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber

CVE-ID: CVE-2026-45458

CWE-ID: CWE-416

Exploitation vector: Remote access

Exploit availability: No public exploit available

Vendor: Microsoft

Affected software:
Microsoft SharePoint Server Subscription Edition
Microsoft SharePoint Enterprise Server
Microsoft SharePoint Server
Microsoft 365 Apps for Enterprise
Microsoft Office
Microsoft Word
Microsoft Office LTSC

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a use-after-free error in Microsoft Outlook and Word. A remote attacker can execute arbitrary code on the target system.

Install updates from vendor's website.

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45458