Web feature developers told to dial up attention on privacy and security

Web feature developers are being warned to step up attention to privacy and security as they design contributions.

Writing in a blog post about "evolving threats" to Internet users' privacy and security, the W3C standards body's technical architecture group (TAG) and Privacy Interest Group (PING) set out a series of revisions to the W3C's Security and Privacy Questionnaire for web feature developers.

The questionnaire itself is not new. But the latest updates place greater emphasis on the need for contributors to assess and mitigate privacy impacts, with developers warned that "features may not be implemented if risks are found impossible or unsatisfactorily mitigated".

In the blog post, independent researcher Lukasz Olejnik, currently serving as an invited expert at the W3C TAG; and Apple's Jason Novak, representing the PING, write that the intent with the update is to make it "clear that feature developers should consider security and privacy early in the feature's lifecycle" [emphasis theirs].

"The TAG will be carefully considering the security and privacy of a feature in their design reviews," they further warn, adding: "A security and privacy considerations section of a specification is more than answers to the questionnaire."

Security & privacy to be considered early in the web/browser feature's lifecycle. New high level type of threat "legitimate misuse": just because something is technically possible does not mean it was designed for abuse and it is OK to do so

- Lukasz Olejnik (@lukOlejnik) September 11, 2019

The revisions to the questionnaire include updates to the threat model and specific threats a specification author should consider - including a new high level type of threat dubbed "legitimate misuse", where the document stipulates that: "When designing a specification with security and privacy in mind, all both use and misuse cases should be in scope."

"Including this threat into the Security and Privacy Questionnaire is meant to highlight that just because a feature is possible does not mean that the feature should necessarily be developed, particularly if the benefitting audience is outnumbered by the adversely impacted audience, especially in the long term," they write. "As a result, one mitigation for the privacy impact of a feature is for a user agent to drop the feature (or not implement it)."

"Features should be secure and private by default and issues mitigated in their design," they further emphasize. "User agents should not be afraid of undermining their users' privacy by implementing new web standards or need to resort to breaking specifications in implementation to preserve user privacy."

The pair also urge specification authors to avoid blanket treatment of first and third parties, suggesting: "Specification authors may want to consider first and third parties separately in their feature to protect user security and privacy."

The revisions to the questionnaire come at a time when browser makers are dialling up their response to privacy threats - encouraged by rising public awareness of the risks posed by data leaks, as well as increased regulatory action on data protection.

Last month the open source WebKit browser engine (which underpins Apple's Safari browser) announced a new tracking prevention policy that takes the strictest line yet on background and cross-site tracking, saying it would treat attempts to circumvent the policy as akin to hacking - essentially putting privacy protection on a par with security.

Earlier this month Mozilla also pushed out an update to its Firefox browser that enables an anti-tracking cookie feature across the board, for existing users too - demoting third party cookies to default junk.

Even Google's Chrome browser has made some tentative steps towards enhancing privacy - announcing changes to how it handles cookies earlier this year. Though the adtech giant has studiously avoided flipping on privacy by default in Chrome where third party tracking cookies are concerned, leading to accusations that the move is mostly privacy-washing.

More recently Google announced a long term plan to involve its Chromium browser engine in developing a new open standard for privacy - sparking concerns it's trying to both kick the can on privacy protection and muddy the waters by shaping and pushing self-interested definitions which align with its core data-mining business interests.

There's more activity to consider too. Earlier this year another data-mining adtech giant, Facebook, made its first major API contribution to Google's Chrome browser - which it also brought to the W3C Performance Working Group.

Facebook does not have its own browser, of course. Which means that authoring contributions to web technologies offers the company an alternative conduit to try to influence Internet architecture in its favor.

The W3C TAG's latest move to focus minds on privacy and security by default is timely.

It chimes with a wider industry shift towards pro-actively defending user data, and should rule out any rubberstamping of tech giants contributions to Internet architecture which is obviously a good thing. Scrutiny remains the best defence against self-interest.