Security Updates for Microsoft Office Web Apps (July 2021)

high Nessus Plugin ID 151608


The Microsoft Office Web Apps installation on the remote host is affected by multiple vulnerabilities.


The Microsoft Office Web Apps installation on the remote host is missing security updates. It is, therefore, affected by the following vulnerabilities:

- Multiple remote code execution vulnerabilities in Microsoft Excel. (CVE-2021-34501, CVE-2021-34518)

- A spoofing vulnerability in Microsoft Office Online Server. (CVE-2021-34451).

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


Microsoft has released the following security updates to address this issue:

See Also

Plugin Details

Severity: High

ID: 151608

File Name: smb_nt_ms21_jul_office_web.nasl

Version: 1.7

Type: local

Agent: windows

Published: 7/13/2021

Updated: 12/29/2023

Supported Sensors: Nessus

Risk Information


Risk Factor: High

Score: 7.4


Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5.6

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

CVSS Score Source: CVE-2021-34518


Risk Factor: High

Base Score: 7.8

Temporal Score: 7.2

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

Temporal Vector: CVSS:3.0/E:F/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:microsoft:office_web_apps

Required KB Items: SMB/MS_Bulletin_Checks/Possible

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 7/13/2021

Vulnerability Publication Date: 7/13/2021

Reference Information

CVE: CVE-2021-34451, CVE-2021-34501, CVE-2021-34518

IAVA: 2021-A-0316-S

MSFT: MS21-5001973, MS21-5001986

MSKB: 5001973, 5001986