Security Updates for Microsoft Office Online Server (January 2020)

medium Nessus Plugin ID 132870
New! Plugin Severity Now Using CVSS v3

The calculated severity for Plugins has been updated to use CVSS v3 by default. Plugins that do not have a CVSS v3 score will fall back to CVSS v2 for calculating severity. Severity display preferences can be toggled in the settings dropdown.


The Microsoft Office Online Server installation on the remote host is missing a security update.


The Microsoft Office Online Server installation on the remote host is missing a security update. It is, therefore, affected by the following vulnerability :

- A spoofing vulnerability exists when Office Online does not validate origin in cross-origin communications correctly. An attacker could exploit the vulnerability by sending a specially crafted request to an affected site. The attacker who successfully exploited the vulnerability could then perform cross-origin attacks on affected systems. These attacks could allow the attacker to read content that the attacker is not authorized to read, and use the victim's identity to take actions on the site on behalf of the victim. The victim needs to be authenticated for an attacker to compromise the victim.
The security update addresses the vulnerability by ensuring that Office Online properly validates origins.


Microsoft has released KB4484223 to address this issue.

See Also

Plugin Details

Severity: Medium

ID: 132870

File Name: smb_nt_ms20_jan_office_web.nasl

Version: 1.3

Type: local

Agent: windows

Published: 1/14/2020

Updated: 1/22/2020

Dependencies: office_installed.nasl, microsoft_owa_installed.nbin, microsoft_office_compatibility_pack_installed.nbin, smb_hotfixes.nasl, ms_bulletin_checks_possible.nasl

Risk Information

CVSS Score Source: CVE-2020-0647


Risk Factor: Low

Score: 2.5


Risk Factor: Medium

Base Score: 5.8

Temporal Score: 4.3

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

Temporal Vector: E:U/RL:OF/RC:C


Risk Factor: Medium

Base Score: 5.4

Temporal Score: 4.7

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

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:microsoft:office_online_server

Required KB Items: SMB/MS_Bulletin_Checks/Possible

Exploit Ease: No known exploits are available

Patch Publication Date: 1/14/2020

Vulnerability Publication Date: 1/14/2020

Reference Information

CVE: CVE-2020-0647

MSKB: 4484223

MSFT: MS20-4484223