CVE-2020-25820 : What You Need to Know

BigBlueButton before 2.2.7 allows remote authenticated users to read local files and conduct SSRF attacks via an uploaded Office document that has a crafted URL in an ODF xlink field.

Understanding CVE-2020-25820

BigBlueButton is vulnerable to remote attacks that can lead to unauthorized access and SSRF exploitation.

What is CVE-2020-25820?

This CVE refers to a security vulnerability in BigBlueButton versions prior to 2.2.7 that enables authenticated remote users to read local files and perform SSRF attacks by uploading an Office document containing a malicious URL in an ODF xlink field.

The Impact of CVE-2020-25820

The exploitation of this vulnerability can result in unauthorized access to sensitive files and the execution of SSRF attacks, potentially leading to further compromise of the system and data.

Technical Details of CVE-2020-25820

BigBlueButton's security flaw is detailed below.

Vulnerability Description

The vulnerability allows authenticated remote users to read local files and conduct SSRF attacks through specially crafted URLs in uploaded Office documents.

Affected Systems and Versions

Product: BigBlueButton
Vendor: N/A
Versions affected: All versions before 2.2.7

Exploitation Mechanism

Remote authenticated users upload an Office document with a malicious URL in an ODF xlink field.

Mitigation and Prevention

Protect your systems from CVE-2020-25820 with the following measures.

Immediate Steps to Take

Upgrade BigBlueButton to version 2.2.7 or newer to mitigate the vulnerability.
Restrict access to the application to trusted users only.
Monitor and review file uploads for malicious content.

Long-Term Security Practices

Regularly update and patch software to address security vulnerabilities.
Conduct security training for users to raise awareness of potential threats.

Patching and Updates

Apply security patches promptly to ensure that known vulnerabilities are addressed.