CVE-2020-1103 — Microsoft SharePoint Information Disclosure Vulnerability
Executive Summary
An information disclosure vulnerability exists where certain modes of the search function in Microsoft SharePoint Server are vulnerable to cross-site search attacks (a variant of cross-site request forgery, CSRF). When users are simultaneously logged in to Microsoft SharePoint Server and visit a malicious web page, the attacker can, through standard browser functionality, induce the browser to invoke search queries as the logged in user. While the attacker can’t access the search results or documents as such, the attacker can determine whether the query did return results or not, and thus by issuing targeted queries discover facts about documents that are searchable for the logged-in user. The security update addresses the vulnerability by running the search queries in a way that doesn’t expose them to this browser vulnerability.
Overview
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
EPSS Score
Affected Products
| Product | KB Article | Severity | Impact | Restart Required |
|---|---|---|---|---|
| Microsoft SharePoint Enterprise Server 2016 | 4484336 (Security Update) |
Important | Information Disclosure | Maybe |
| Microsoft SharePoint Foundation 2013 Service Pack 1 | 4484364 (Security Update) |
Important | Information Disclosure | Maybe |
| Microsoft SharePoint Server 2019 | 4484332 (Security Update) |
Important | Information Disclosure | Maybe |
Patches
| Article | Type | Restart |
|---|---|---|
4484336 |
Security Update | Maybe |
4484364 |
Security Update | Maybe |
4484332 |
Security Update | Maybe |
Known Exploits
Acknowledgments
Oleksandr Mirosh (@olekmirosh) from Micro Focus Fortify