Security Updates for Microsoft Word Products C2R (May 2026)

high Nessus Plugin ID 314674

Synopsis

The Microsoft Word Products are affected by multiple vulnerabilities.

Description

The Microsoft Word Products are missing security updates. It is, therefore, affected by multiple vulnerabilities:

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

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

- 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 patches to address these issues.

For Office 365, Office 2016 C2R, or Office 2019, ensure automatic updates are enabled or open any office app and manually perform an update.

See Also

http://www.nessus.org/u?5931548c

Plugin Details

Severity: High

ID: 314674

File Name: smb_nt_ms26_may_word_c2r.nasl

Version: 1.1

Type: Local

Agent: windows

Family: Windows

Published: 5/14/2026

Updated: 5/14/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Critical

Score: 9.0

CVSS v2

Risk Factor: High

Base Score: 7.2

Vector: CVSS2#AV:L/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

CVSS Score Source: CVE-2026-40361

Vulnerability Information

CPE: cpe:/a:microsoft:word

Required KB Items: SMB/MS_Bulletin_Checks/Possible

Exploit Ease: No known exploits are available

Patch Publication Date: 5/13/2026

Vulnerability Publication Date: 5/13/2026

Reference Information

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