CVE-2021-22917 : Vulnerability Insights and Analysis

Brave Browser Desktop versions 1.17 to 1.20 are susceptible to information disclosure due to DNS requests in Tor windows bypassing Tor when adblocking is active.

Understanding CVE-2021-22917

This CVE highlights the risk of sensitive data exposure in Brave Browser Desktop versions 1.17 to 1.20.

What is CVE-2021-22917?

CVE-2021-22917 exposes a vulnerability in Brave Browser that allows DNS requests in Tor windows to leak information if adblocking is enabled.

The Impact of CVE-2021-22917

The vulnerability can lead to unauthorized access to user information and compromise privacy when using the affected versions of the Brave Browser.

Technical Details of CVE-2021-22917

The technical aspects of the CVE include:

Vulnerability Description

The vulnerability arises from DNS requests not passing through Tor in specific browser windows, potentially revealing user data.

Affected Systems and Versions

Brave Browser Desktop versions 1.17 to 1.20 are impacted by this vulnerability.

Exploitation Mechanism

Exploiting this vulnerability involves leveraging the issue of DNS requests bypassing Tor in Tor windows with adblocking enabled.

Mitigation and Prevention

To address CVE-2021-22917, consider the following:

Immediate Steps to Take

Update Brave Browser to version 1.20 or later to fix the information disclosure vulnerability.
Disable adblocking in Tor windows as a temporary mitigation measure.

Long-Term Security Practices

Regularly update your web browsers to the latest versions to prevent known vulnerabilities.
Implement a robust adblocking solution that doesn't interfere with Tor network functionality.

Patching and Updates

Stay informed about security patches and updates released by Brave Browser to address CVE-2021-22917 and other potential security risks.