CVE-2020-1101 Explained : Impact and Mitigation

Microsoft SharePoint Server XSS Vulnerability

Understanding CVE-2020-1101

A cross-site-scripting (XSS) vulnerability in Microsoft SharePoint Server could allow attackers to execute malicious scripts on the affected system.

What is CVE-2020-1101?

This vulnerability arises when SharePoint Server fails to adequately sanitize a specific type of web request, potentially leading to XSS attacks.

The Impact of CVE-2020-1101

Attackers can inject malicious scripts into web pages viewed by users, leading to unauthorized actions or data theft.
Successful exploitation could compromise sensitive data stored in SharePoint.

Technical Details of CVE-2020-1101

Vulnerability Description

The vulnerability stems from inadequate sanitization of specially crafted web requests, leaving the system open to XSS attacks.

Affected Systems and Versions

Microsoft SharePoint Enterprise Server 2016
Microsoft SharePoint Server 2019
Microsoft SharePoint Foundation 2013 Service Pack 1

Exploitation Mechanism

Attackers craft malicious web requests containing scripts.
These requests are submitted to the vulnerable SharePoint server.
If successful, the scripts execute in the context of the user's browser.

Mitigation and Prevention

Immediate Steps to Take

Apply the latest security updates provided by Microsoft.
Implement proper input validation and output encoding in web applications.
Monitor web traffic and user inputs for suspicious activities.

Long-Term Security Practices

Regularly update and patch SharePoint servers to address known vulnerabilities.
Conduct periodic security audits and penetration testing to identify and remediate security weaknesses.
Educate users and administrators about safe browsing practices and awareness of phishing attempts.

Patching and Updates

Ensure that all SharePoint servers are regularly updated with the latest security patches from Microsoft.