Brave, the open source privacy- focussed browser, has allegedly introduced a ‘backdoor’ to remotely inject headers in HTTP requests that may track users, say users on HackerNews.
Users on Twitter and HackerNews have expressed their concerns over the new update on custom HTTP headers added by the Brave team:
— Rafael Rivera (@WithinRafael) February 10, 2019
A user on Reddit has explained this move as “not tracking anything, they just send the word “Brave” to the website whenever you visit certain partners of theirs. So for instance visiting coinbase.com sends an “X-Brave-Partner” custom header to coinbase.com.”
Brendan Eich, from the Brave team, has replied back to this allegation saying that the ‘Update is not a “backdoor” in any event and is a custom header instead.’ He says the update is about custom HTTP headers that Brave sends to its partners, with fixed header values. There is no tracking hazard in the new update. He further stresses on the fact that Brave blocks 3rd party cookies and storage and 3rd party fingerprinting along with HSTS supercookies; thus assuring users on preserving their privacy. “I find it silly to assume we will “heel turn” so obviously and track our users. C’mon! We defined our model so we can’t cheat without losing lead users who would see through it. That requires seeing clearly things like the difference between tracking and script blocking or custom header sending, though.”
Users have also posted on Hacker News that the Brave browser Tracking Protection feature does not block tracking scripts from hostnames associated with Facebook and Twitter. The tracking_protection_service.h file contains a comment informing that a tracking protection white_list variable was created as a “Temporary hack which matches both browser-laptop and Android code”. Bleepingcomputer also reports that this whitelist variable is associated with code in the tracking_protection_service.cc file that adds various Facebook and Twitter hostnames to the whitelist variable so that they are not blocked by Brave’s Tracking Protection feature. In response to this comment, Brave says that the issue that was opened on September 8th, 2018 and developers decided to whitelist tracking scripts from Facebook and Twitter because blocking them would “affect the functionality of many sites” including Facebook logins.
You can head over to Brendan’s Reddit thread for more insights on this update.