Security Updates for Microsoft SharePoint Server (September 2018)

Critical Nessus Plugin ID 117425

Synopsis

The Microsoft SharePoint Server installation on the remote host is affected by multiple vulnerabilities.

Description

The Microsoft SharePoint Server installation on the remote host is missing security updates. It is, therefore, affected by multiple vulnerabilities :

- An elevation of privilege vulnerability exists when Microsoft SharePoint Server does not properly sanitize a specially crafted web request to an affected SharePoint server. An authenticated attacker could exploit the vulnerability by sending a specially crafted request to an affected SharePoint server. The attacker who successfully exploited the vulnerability could then perform cross-site scripting attacks on affected systems and run script in the security context of the current user. These attacks could allow the attacker to read content that the attacker is not authorized to read, use the victim's identity to take actions on the SharePoint site on behalf of the user, such as change permissions and delete content, and inject malicious content in the browser of the user. The security update addresses the vulnerability by helping to ensure that SharePoint Server properly sanitizes web requests. (CVE-2018-8428, CVE-2018-8431)

- A cross-site-scripting (XSS) vulnerability exists when Microsoft SharePoint Server does not properly sanitize a specially crafted web request to an affected SharePoint server. An authenticated attacker could exploit the vulnerability by sending a specially crafted request to an affected SharePoint server. The attacker who successfully exploited the vulnerability could then perform cross-site scripting attacks on affected systems and run script in the security context of the current user. The attacks could allow the attacker to read content that the attacker is not authorized to read, use the victims identity to take actions on the SharePoint site on behalf of the user, such as change permissions and delete content, and inject malicious content in the browser of the user. The security update addresses the vulnerability by helping to ensure that SharePoint Server properly sanitizes web requests. (CVE-2018-8426)

Solution

Microsoft has released the following security updates to address this issue:
-KB4092459
-KB4092470
-KB4022207

See Also

http://www.nessus.org/u?b788a1ee

http://www.nessus.org/u?5999379b

http://www.nessus.org/u?94c0437b

Plugin Details

Severity: Critical

ID: 117425

File Name: smb_nt_ms18_sep_office_sharepoint.nasl

Version: 1.3

Type: local

Agent: windows

Published: 2018/09/11

Modified: 2018/09/17

Dependencies: 93232, 13855, 57033, 74250

Risk Information

Risk Factor: Critical

CVSS Score Source: manual

CVSS Score Rationale: Score based on analysis of the vendor advisory.

CVSSv2

Base Score: 10

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

CVSSv3

Base Score: 9.8

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

Vulnerability Information

CPE: cpe:/a:microsoft:sharepoint

Required KB Items: SMB/MS_Bulletin_Checks/Possible

Patch Publication Date: 2018/09/11

Vulnerability Publication Date: 2018/09/11

Reference Information

CVE: CVE-2018-8426, CVE-2018-8428, CVE-2018-8431

MSKB: 4092459, 4092470, 4022207

MSFT: MS18-4092459, MS18-4092470, MS18-4022207

IAVA: 2018-A-0291, 2018-A-0293