CVE-2021-21323 MEDIUM

CVE-2021-21323: Regression in DNS leakage from Tor windows

Vendor Brave
Product brave-browser
Weakness CWE-200 · Info exposure
Published February 23, 2021
Last update August 3, 2024
View on NVD All CVEs

CVSS base score

4.3/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction Required
Confidentiality Low
Integrity None

CVSS vector

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

What the vulnerability does

01Description

Brave is an open source web browser with a focus on privacy and security. In Brave versions 1.17.73-1.20.103, the CNAME adblocking feature added in Brave 1.17.73 accidentally initiated DNS requests that bypassed the Brave Tor proxy. Users with adblocking enabled would leak DNS requests from Tor windows to their DNS provider. (DNS requests that were not initiated by CNAME adblocking would go through Tor as expected.) This is fixed in Brave version 1.20.108

Key dates

02Disclosure timeline

February 23, 2021 CVE published
August 3, 2024 Record updated