Simon Willison’s Weblog

28 items tagged “privacy”

Using achievement stats to estimate sales on steam (via) Really interesting data leak exploit here: Valve’s Steam API was showing the percentage of users that gained a specific achievement up to 16 decimal places—which inadvertently leaked their exact usage statistics, since if 0.012782207690179348 percent of players get an achievement the only possible input is 8 players out of 62,587. # 9th August 2018, 9:03 am

Cookies-over-HTTP Bad (via) Mike West from the Chrome security team proposes a way for browsers to start discouraging the use of tracking cookies sent over HTTP—which represent a significant threat to user privacy from network attackers. It’s a clever piece of thinking: browsers would slowly ramp up the forced expiry deadline for non-HTTPS cookies, further encouraging sites to switch to HTTPS cookies while giving them ample time to adapt. # 7th April 2018, 2:39 pm

Protecting Against HSTS Abuse (via) Any web feature that can be used to persist information will eventually be used to build super-cookies. In this case it’s HSTS—a web feature that allows sites to tell browsers “in the future always load this domain over HTTPS even if the request specified HTTP”. The WebKit team caught this being exploited in the wild, by encoding a user identifier in binary across 32 separate sub domains. They have a couple of mitigations in place now—I expect other browser vendors will follow suit. # 19th March 2018, 10:21 pm

What we need to do is come up with a way to help people understand that there are ways to never be lost again, and to listen to any music you want, and to video chat with someone on the other side of the world, without them having to feel disquieted about it. That it’s not OK that you’re made to feel weirded out. That it’s possible for there to be alternatives. That having to feel someone rooting around in your life is not a price you should have to pay.

Stuart Langridge # 1st February 2018, 2:03 pm

Facebook’s Instant Personalization: An Analysis of Fundamental Privacy Flaws (via) Oh FFS. “Instant Personalization” means you visit one of Facebook’s “partner websites” and Facebook instantly tells them your full identity and gives them access to full Facebook connect functionality—without you performing any action other than visiting the site. This will not end well. # 2nd October 2010, 11:53 pm

Why do some people disable JavaScript in their browser?

For security reasons.

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The Evolution of Privacy on Facebook. Brilliant infographic showing exactly how the visibility of different aspects of your Facebook profile has changed in increments since 2005. Also a nice example of Processing.js in action. # 9th May 2010, 11:53 am

The new Facebook API exposes the events you attend to anyone on the Internet. I’m generally impressed by the new set of Facebook APIs—they’re a whole lot easier to work with than the older stuff—but they’re also clearly a bit half-baked and the privacy model needs some urgent work. The Graph API allows to to see all “open” events that any user has attended or is attending, which can exposes things like their friend’s home addresses. Yes, this means you can stalk Mark Zuckerberg. # 26th April 2010, 12:08 pm

A new Buzz start-up experience based on your feedback. Buzz is switching to the more obvious model: use existing Gmail behaviour to suggest a list of people to follow, rather than auto-following them. It feels pretty clear to me that this is how following recommendations should work. # 14th February 2010, 10:12 am

WARNING: Google Buzz Has A Huge Privacy Flaw. Interesting one this: by default, Buzz creates a public profile for you that lists the people you follow—but your default set of followers is derived from the people you contact most frequently using Gmail. This means users of Buzz may inadvertently reveal their most frequent contacts, which is an issue for people like journalists with anonymous sources, unhappy employees seeking new work or even people having e-mail based affairs. # 11th February 2010, 11:30 am

Google Dashboard. New Google product which shows exactly how much information Google have stored against your account, all on one page. This is a really useful tool, and hopefully will help set a powerful precedent for other sites to follow. # 5th November 2009, 2:03 pm

You Deleted Your Cookies? Think Again (via) Flash cookies last longer than browser cookies and are harder to delete. Some services are sneakily “respawning” their cookies—if you clear the regular tracking cookie it will be reinstated from the Flash data next time you visit a page. # 17th August 2009, 3:23 pm

TOSBack | The Terms-Of-Service Tracker. Fantastic idea (and implementation) from the EFF—a site that currently tracks 44 website policy documents and highlights changes to them using a diff engine (from Drupal). A global RSS feed is available—it would be useful if individual feeds for different sites and organisations were also provided. # 7th June 2009, 10:49 am

On the Anonymity of Home/Work Location Pairs. Most people can be uniquely identified by the rough location of their home combined with the rough location of their work. US Census data shows that 5% of people can be uniquely identified by this combination even at just census tract level (1,500 people). # 24th May 2009, 1:14 pm

For the record, I’m a noted privacy freak and I don’t pretend to speak for anyone else on this topic. I know that resistance is futile. I continue to believe that there is a great divide on sensitivity about privacy—you’ve either had your identity stolen or been stalked or had some great intrusion you couldn’t fend off, or you haven’t. I’m in the former camp and it colors the way I view and think about privacy online. It makes me indescribably sad to see how clearly I and others in my camp are losing this battle.

Marc Hedlund # 13th May 2009, 8:41 am

eval() Kerfuffle. The ability to read supposedly private variables in Firefox using a second argument to eval() will be removed in Firefox 3.1. # 2nd July 2008, 9:24 pm

Since 9/11, approximately three things have potentially improved airline security: reinforcing the cockpit doors, passengers realizing they have to fight back and—possibly—sky marshals. Everything else—all the security measures that affect privacy—is just security theater and a waste of effort.

Bruce Schneier # 29th January 2008, 12:14 pm

Google Reader ruins Christmas (via) New sharing feature automatically reveals shared items to Gmail contacts, causing political rows. # 25th December 2007, 2:59 pm

Deconstructing Facebook Beacon JavaScript. How Facebook’s new Beacon service (also known as “Facebook ruined Christmas”) actually works. # 25th November 2007, 9:20 pm

Is Facebook Really Censoring Search When It Suits Them? Apparently MoveOn’s group “Petition: Facebook, stop invading my privacy!” stopped showing up in search results for “privacy”—the search claimed 17 results but suspiciously only showed 16. # 23rd November 2007, 7:50 am

Amazon Gets an SLA (But I Still Can’t Use It). “Ontario’s Freedom of Information and Protection of Privacy Acts (FIPPA) don’t allow me to store sensitive information (e.g., students’ work) in jurisdictions that permit secret warrants, like those mandated by the USA PATRIOT Act.” # 9th October 2007, 3 pm

Designing for a security breach

User account breaches are inevitable. We should take that in to account when designing our applications.

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Firefox 3 Antiphishing Sends Your URLs To Google. Stories like this crop up every now and then, but no one ever seems to mention that the Google Toolbar has been doing this since it was released (more than five years ago) provided you have PageRank display turned on. # 25th September 2007, 11:04 pm

Sun’s OpenID IdP: Real vs Fake. The thinking behind Sun’s decision to allow users of their OpenID provider to pick fake names and assign personal e-mail addresses. # 25th September 2007, 10:39 pm

Sun’s OpenID IdP: Data Governance. Lauren Wood explains the checklist used to ensure Sun’s OpenID provider adequately respected user privacy and data governance (what happens to the data that is stored). # 22nd September 2007, 8:50 pm

It’s still a privacy concern. If, for example, I work at and post from Microsoft all day and my identicon is that of the MS Proxy Server then I would be able to identify other mefi users who are my co-workers because our identicons would match.

vacapinta # 29th January 2007, 4:12 am

Visual Security: 9-block IP Identification. Smart (and pretty) trick for showing a representation tied to a commenter’s IP address without affecting their privacy. # 18th January 2007, 4:55 pm

non-consensual http user tracking using caches. Interesting security issue involving HTTP caching headers # 20th January 2004, 10:37 pm