Detections
Analytics

Security Updates for Microsoft Word Products (May 2026)

high Nessus Plugin ID 314343

Synopsis

The Microsoft Word Products are affected by multiple vulnerabilities.

Description

The Microsoft Word Products are missing a security update. They are, therefore, affected by multiple vulnerabilities:

 - Access of resource using incompatible type ('type confusion') in Microsoft Office Word allows an unauthorized attacker to execute code locally. (CVE-2026-40364)

 - Use after free in Microsoft Office Word allows an unauthorized attacker to execute code locally.
 (CVE-2026-40361, CVE-2026-40366)

 - Untrusted pointer dereference in Microsoft Office Word allows an unauthorized attacker to execute code locally. (CVE-2026-40367)

 - Files or directories accessible to external parties in Microsoft Office Word allows an unauthorized attacker to disclose information locally. (CVE-2026-35440)

 - External control of file name or path in Microsoft Office Word allows an unauthorized attacker to disclose information over a network. (CVE-2026-40421)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Microsoft has released KB5002858 to address this issue.

See Also

https://support.microsoft.com/en-us/help/5002858

Plugin Details

Severity: High

ID: 314343

File Name: smb_nt_ms26_may_word.nasl

Version: 1.1

Type: Local

Agent: windows

Published: 5/12/2026

Updated: 5/12/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

CVSS v2

Risk Factor: Critical

Base Score: 10

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2026-40361

CVSS v3

Risk Factor: High

Base Score: 8.4

Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Vulnerability Information

CPE: cpe:/a:microsoft:word

Required KB Items: SMB/MS_Bulletin_Checks/Possible

Patch Publication Date: 5/12/2026

Vulnerability Publication Date: 5/12/2026

Reference Information

CVE: CVE-2026-35440, CVE-2026-40361, CVE-2026-40364, CVE-2026-40366, CVE-2026-40367, CVE-2026-40421

MSFT: MS26-5002858

MSKB: 5002858