Microsoft SharePoint Server Spoofing Vulnerability

Source data

Overview

Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Office SharePoint allows an authorized attacker to perform spoofing over a network.

Impact & technical details

Spoofing

How could an attacker exploit the vulnerability? An attacker who successfully exploited this vulnerability might be able to run their scripts in the security context of the current user by enticing the user to click on a link resulting in a cross-site scripting attack on the SharePoint Server.

I am running SharePoint Server 2016. Do the updates for SharePoint Enterprise Server 2016 also apply to the version I am running? Yes. The same KB number applies to both SharePoint Server 2016 and SharePoint Enterprise Server 2016. Customers running either version should install the security update to be protected from this vulnerability.

According to the CVSS metric, user interaction is required (UI:R) and privileges required is low (PR:L). What does that mean for this vulnerability? An authorized attacker must send the user a malicious link and convince the user to open it.

According to the CVSS metrics, successful exploitation of this vulnerability could lead to some loss of confidentiality (C:L), and integrity (I:L) but lead to no loss of availability (A:N). What is the impact of this vulnerability? An attacker who successfully exploited the vulnerability could view some sensitive information (Confidentiality), make changes to disclosed information (Integrity), but cannot limit access to the resource (Availability).

There are multiple update packages available for some of the affected software. Do I need to install all the updates listed in the Security Updates table for the software? Yes. Customers should apply all updates offered for the software installed on their systems. If multiple updates apply, they can be installed in any order.

CVSS base score

4.6 / 10

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C

Highest base score supplied by MSRC for this record; the vector belongs to that score. Ratings can vary by product. Microsoft Important is displayed as High; Moderate is displayed as Medium.

Affected products

• Microsoft SharePoint Enterprise Server 2016
• Microsoft SharePoint Server 2019
• Microsoft SharePoint Server Subscription Edition

Source guidance

Remediation

The source provides update references without a separate remediation summary. Review the applicable update links below.

At least one Microsoft vendor-fix reference is available. Check each affected product for its applicable update, prerequisites, and supported version.

Authoritative sources & updates

Findings and update information come from the linked publishers. GTP compiles the public record and provides the recommendation above. CVSS ratings shown here come from Microsoft. NVD references provide additional public context.

• Microsoft Security Response Center (opens in a new tab)
• Microsoft security update · 5002905 (opens in a new tab)
• Microsoft remediation guidance (opens in a new tab)
• Microsoft security update · 5002906 (opens in a new tab)
• Microsoft remediation guidance (opens in a new tab)
• Microsoft security update · 5002894 (opens in a new tab)
• Microsoft remediation guidance (opens in a new tab)
• Microsoft security update · 5002896 (opens in a new tab)
• Microsoft remediation guidance (opens in a new tab)
• Microsoft security update · 5002893 (opens in a new tab)
• Microsoft remediation guidance (opens in a new tab)