Panopticlick 3.0

  • Today we’re launching a new version of Panopticlick, an EFF site which audits your browser privacy protection. Conceived to raise awareness about the threat of device fingerprinting, Panopticlick was extended in December 2015 to check for protection against tracking by ads and invisible beacons. This new update adds a test for trackers whitelisted by the so-called “Acceptable Ads” initiative. Acceptable Ads is a program involving the popular adblockers Adblock Plus and Adblock, whereby companies can have their ads deemed “acceptable” if they meet certain format criteria. These ads are then unblocked and any company operating above a certain threshold must agree to pay Eyeo, the owner of Adblock Plus, a fee of 30% of the resulting revenue from the ads for administering the process. This revenue is divided between the participating ad blockers.

    By default, Panopticlick will now check browsers for trackers from the Acceptable Ads list by testing against a real tracker. If the browser fails, that tracker will receive some information about the user, but this minimal leakage is necessary to diagnose the problem. If you are uncomfortable with this, it is possible to opt out of the test. If Panopticlick detects inadequate protection, the user is linked to instructions to disable Acceptable Ads and fix their configuration.

    What is Acceptable Ads**?**

    Acceptable Ads is a whitelist of “non-intrusive” ads that meet requirements relating to format, size and placement on the page. The process has been operated on a for-profit basis since late 2011 by Eyeo. Large advertising companies like Amazon, Criteo, and Google make significant payments to this program, though the exact amounts are not public. Acceptable Ads serves an important policy purpose by identifying types of ads that are not visually intrusive. However, the payments that Eyeo demands for listings, and the fact that Eyeo has implemented Acceptable Ads in such a way that it silently overrides users’ privacy settings, are huge problems.

    The Problem with Ad Blockers as Privacy Tools

    Many users install blockers not just to block obtrusive advertising but also for privacy and security reasons. Unlike tracker blockers (like Brave, Disconnect, Privacy Badger, or uBlock Origin), ad blockers offer only limited privacy protection by default. This functionality is easily extended through the addition of filters such as EasyPrivacy, a blacklist of invisible trackers. But since the launch of the Acceptable Ads Initiative in late 2011, the Acceptable Ads whitelist has been turned on by default for Adblock Plus users, as it has been for Adblock users since late 2015. The Acceptable Ads whitelist allows numerous tracking domains. Content blockers like Adblock Plus and Adblock function based on both whitelists and blacklists. When there is a conflict, the whitelist wins. This means that even though EasyPrivacy is intentionally installed and Acceptable Ads is enabled by default, whitelisted domains will not be blocked from tracking the user. With more than 10,000 domains on the Acceptable Ads whitelist, that’s a lot of tracking.

    Who Benefits?

    Proper protection is only possible if users disable the default Acceptable Ads whitelist, but this is not made clear. As a consequence, we believe many users have been unwittingly exposed to tracking. Because the Acceptable Ads whitelist is enabled by default, and no warning is offered regarding the incompatibility of the two filter lists, EasyPrivacy users are left unaware that Acceptable Ads is undermining their preferences. This is despite the fact that tracker blocking was offered by ABP as an explicit option during installation until recently, and Adblock offers EasyPrivacy in the list of filters available for activation in its user settings. In reality, the co-existence of these two options could only be logically consistent were EasyPrivacy to restrict the domains allowed from the Acceptable Ads list to those which are privacy-compliant. A setting just released for Adblock Plus on Firefox offers this option, but its details are still to be verified. 1 The failure to offer users clear guidance, combined with bad interface design, has facilitated user error and undermined user privacy. This has been going on for years and likely involves millions of users.

    Dark Patterns

    This problem can be solved with better user interface design and clear information, that clearly outlines the different configuration options to users during installation. Better still, clients could offer a one-click option to enable meaningful privacy protection as part of the installation process, where most users are most likely to choose it. Otherwise, we know that only a minority of users change the default configuration of their software. Regardless of what options are available, the default options are key to how any software will be used in the wild. Manipulating defaults and interface design to influence user actions is a practice referred to as “dark patterns”. An explanation for such behavior is close at hand: every user who opts out of Acceptable Ads represents a loss of income for the companies involved, which are simultaneously ad blockers and brokers of their users’ eyeballs.

    Serve the User?

    Earlier this year, Eyeo handed over control of the criteria for Acceptable Ads to an independent committee, though Eyeo remains in control of the business operation. In principle, this committee could serve the important public function of setting standards for visual unobtrusiveness, privacy-friendliness, and other types of good practice for online and mobile ads. 2 It could also be an important forum to encourage advertisers to switch to privacy-positive technologies compliant with the Do Not Track policy. But the manner in which Acceptable Ads has operated reveals a conflict between the interests of the companies participating in the Acceptable Ads program and those of their users. To resolve this, the issues we identify above must be fixed quickly and comprehensively.

    Defenders of Acceptable Ads have argued that its rationale is to protect the user experience while allowing publishers to sustain themselves through advertising. This is a vital discussion and one in which EFF is keen to participate. Adblock Plus is free to try to persuade the public of the social value of Acceptable Ads for supporting publishers, but it must do so in the context of clear and non-confusing user interface choices for their users and resist the temptation to overturn clear user decisions after the fact. In the meantime, users who want to protect their privacy should either follow our configuration instructions or consider switching to more robust tracker blocking tools.

    • 1. ABP on Firefox’s new settings offers the option of enabling both ‘Acceptable Ads’ and ‘Only allow ads without third-party tracking’. Their FAQ explains that this means ads which either comply with DNT or are served by the site being visited itself.
    • 2. A full discussion of the policy problems that could reasonably be addressed by standards and blocking/unblocking mechanisms in the online advertising space is beyond the scope of this post. However it certainly includes privacy (which EFF has worked on with our Do Not Track standard); visual intrusiveness (which is what Acceptable Ads was designed to address); protection against malvertising (the OTA Alliance has done excellent work on this problem; and landing page quality (which is an issue that Google itself measures with algorithms).

Log in to reply

Tmux Commands

screen and tmux

A comparison of the features (or more-so just a table of notes for accessing some of those features) for GNU screen and BSD-licensed tmux.

The formatting here is simple enough to understand (I would hope). ^ means ctrl+, so ^x is ctrl+x. M- means meta (generally left-alt or escape)+, so M-x is left-alt+x

It should be noted that this is no where near a full feature-set of either group. This - being a cheat-sheet - is just to point out the most very basic features to get you on the road.

Trust the developers and manpage writers more than me. This document is originally from 2009 when tmux was still new - since then both of these programs have had many updates and features added (not all of which have been dutifully noted here).

Action tmux screen
start a new session tmux OR
tmux new OR
tmux new-session
re-attach a detached session tmux attach OR
tmux attach-session
re-attach an attached session (detaching it from elsewhere) tmux attach -d OR
tmux attach-session -d
screen -dr
re-attach an attached session (keeping it attached elsewhere) tmux attach OR
tmux attach-session
screen -x
detach from currently attached session ^b d OR
^b :detach
^a ^d OR
^a :detach
rename-window to newname ^b , <newname> OR
^b :rename-window <newn>
^a A <newname>
list windows ^b w ^a w
list windows in chooseable menu ^a "
go to window # ^b # ^a #
go to last-active window ^b l ^a ^a
go to next window ^b n ^a n
go to previous window ^b p ^a p
see keybindings ^b ? ^a ?
list sessions ^b s OR
tmux ls OR
tmux list-sessions
screen -ls
toggle visual bell ^a ^g
create another window ^b c ^a c
exit current shell/window ^d ^d
split window/pane horizontally ^b " ^a S
split window/pane vertically ^b % ^a |
switch to other pane ^b o ^a <tab>
kill the current pane ^b x OR (logout/^D)
collapse the current pane/split (but leave processes running) ^a X
cycle location of panes ^b ^o
swap current pane with previous ^b {
swap current pane with next ^b }
show time ^b t
show numeric values of panes ^b q
toggle zoom-state of current pane (maximize/return current pane) ^b z
break the current pane out of its window (to form new window) ^b !
re-arrange current panels within same window (different layouts) ^b [space]
Kill the current window (and all panes within) ^b killw [target-window]
  • Criteo is an ad company. You may not have heard of them, but they do retargeting, the type of ads that pursue users across the web, beseeching them to purchase a product they once viewed or have already bought. To identify users across websites, Criteo relies on cross-site tracking using cookies and other methods to follow users as they browse. This has led them to try and circumvent the privacy features in Apple’s Safari browser which protects its users from such tracking. Despite this apparently antagonistic attitude towards user privacy, Criteo has also been whitelisted by the Acceptable Ads initiative. This means that their ads are unblocked by popular adblockers such as Adblock and Adblock Plus. Criteo pays Eyeo, the operator of Acceptable Ads, for this whitelisting and must comply with their format requirements. But this also means they can track any user of these adblockers who has not disabled Acceptable Ads, even if they have installed privacy tools such as EasyPrivacy with the intention of protecting themselves. EFF is concerned about Criteo’s continued anti-privacy actions and their continued inclusion in Acceptable Ads.

    Safari Shuts out Third Party Cookies…

    All popular browsers give users control over who gets to set cookies, but Safari is the only one that blocks third-party cookies (those set by a domain other than the site you are visiting) by default. (Safari’s choice is important because only 5-10% of users ever change default settings in software.) Criteo relies on third-party cookies. Since users have little reason to visit Criteo’s own website, the company gets its cookies onto users’ machines through its integration on many online retail websites. Safari’s cookie blocking is a major problem for Criteo, especially given the large and lucrative nature of iPhone’s user base. Rather than accept this, Criteo has repeatedly implemented ways to defeat Safari’s privacy protections.

    One workaround researchers detected Criteo using was to redirect users from sites where their service was present to their own. For example, if you visited and clicked on a product category, you would be first diverted to and then redirected to Although imperceptible to the user, this detour was enough to persuade the browser that is a site you chose to visit, and therefore a first party entitled to set a cookie rather than a third party. Criteo applied for a patent on this method in August 2013.

    …And Closes the Backdoor

    Last summer, however, Apple unveiled a new version of Safari with more sophisticated cookie handling—called Intelligent Tracking Prevention (ITP)—which killed off the redirect technique as a means to circumvent the cookie controls. The browser now analyzes if the user has engaged with a website in a meaningful way before allowing it to set a cookie. The announcement triggered panic among advertising companies, whose trade association, the Interactive Advertising Bureau, denounced the feature and rushed out technical recommendations to work around it. Obviously the level of user “interaction” with Criteo during the redirect described above fails ITP’s test, which meant Criteo was locked out again.

    It appears that Criteo’s response was to abandon cookies for Safari users and to generate a persistent identifier by piggybacking on a key user safety technology called HSTS. When a browser connects to a site via HTTPS (i.e. a site that supports encryption), the site can respond with an HTTP Strict Transport Security policy (HSTS), instructing the browser to only contact it using HTTPS. Without a HSTS policy, your browser might try to connect to the site over regular old unencrypted HTTP in the future—and thus be vulnerable to a downgrade attack. Criteo used HSTS to sneak data into the browser cache to produce an identifier it could use to recognize the individual’s browser and profile them. This approach relied on the fact that it is difficult to clear HSTS data in Safari, requiring the user to purge the cache entirely to delete the identifier. For EFF, it is especially worrisome that Criteo used a technique that pits privacy protection against user security interests by targeting HSTS. Use of this mechanism was documented by Gotham City Research, an investment firm who have bet against Criteo’s stock.

    In early December, Apple released an update to iOS and Safari which disabled Criteo’s ability to exploit HSTS. This led to Criteo revising down their revenue forecasts and a sharp fall in their share price.

    How is Criteo Acceptable Advertising”****?

    "… w__e sort of seek the consent of users, just like we had done before_."__1_ - Erich Eichmann, CEO Criteo

    _"Only users who don’t already have a Criteo identifier will see the header or footer, and it is displayed only once per device. Thanks to [the?] Criteo advertisers network, most of your users would have already accepted our services on the website of another of our partner. On average, only 5% of your users will see the headers or footers, and for those who do, the typical opt-out rate is less than .2%._" - Criteo Support Center

    Criteo styles itself as a leader in privacy practices, yet they have dedicated significant engineering resources to circumventing privacy tools. They claim to have obtained user consent to tracking based on a minimal warning delivered in what we believe to be a highly confusing context. When a user first visits a site containing Criteo’s script, they received a small notice stating, _"_Click any link to use Criteo’s cross-site tracking technology." If the user continues to use the site, they are deemed to have consented. Little wonder that Criteo can boast of a low opt-out rate to their clients.

    Due to their observed behaviour prior to the ITP episode, Criteo’s incorporation into the Acceptable Ads in December 2015 aroused criticism among users of ad blockers. We have written elsewhere about how Acceptable Ads creates a clash of interests between adblocking companies and their users, especially those concerned with their privacy. But Criteo’s participation in Acceptable Ads brings into focus the substantive problem with the program itself. The criteria for Acceptable Ads are concerned chiefly with format and aesthetic aspects (e.g. How big is the ad? How visually intrusive? Does it blink?) and excludes privacy concerns. Retargeting is unpopular and mocked by users, in part because it wears its creepy tracking practices on its sleeve. Our view is that Criteo’s bad behavior should exclude its products from being deemed “acceptable” in any way.

    The fact that the Acceptable Ads Initiative has approved Criteo’s user-tracking-by-misusing-security-features ads is indicative of the privacy problems we believe to be at the heart of the Acceptable Ads program. In March this year, Eyeo announced an Acceptable Ads Committee that will control the criteria for Acceptable Ads in the future. The Committee should start by instituting a rule which excludes companies that circumvent explicit privacy tools or exploit user security technologies for the purpose of tracking.


    read more
  • Have you ever sent a motivational text to a friend? If you have, perhaps you tailored your message to an activity or location by saying “Good luck in the race!” or “Have fun in New York!” Now, imagine doing this automatically with a compuuuter. What a great invention. Actually, no. That’s not a good invention, it’s our latest Stupid Patent of the Month.

    U.S. Patent No. 9,069,648 is titled “Systems and methods for delivering activity based suggestive (ABS) messages.” The patent describes sending “motivational messages,” based “on the current or anticipated activity of the user,” to a “personal electronic device.” The patent provides examples such as sending the message “don’t give up” when the user is running up a hill. The examples aren’t limited to health or exercise. For example, the patent suggests sending messages like “do not fear” and “God is with you” when a “user enters a dangerous neighborhood.”

    The patent’s description of its invention is filled with silly, non-standard acronyms like ABS for “activity based suggestive” messages or EBIF for “electronic based intelligence function.” These silly acronyms create an illusion of complexity where plain, descriptive language would reveal the mundane nature of the supposed invention. For example, what the patent grandly calls EBIF appears to be nothing more than standard computer processing.

    The ’648 patent is owned by Motivational Health Messaging LLC. While this may be a new company, at least one of the people behind it has been involved in massive patent trolling campaigns before. And the two named inventors have both been inventors on patents that trolls have asserted hundreds of times. One is also an inventor listed on patents asserted by infamous patent troll Shipping and Transit LLC. The other named inventor is the inventor on the patents asserted by Electronic Communication Technologies LLC. Those two entities (with their predecessors) brought over 700 lawsuits, many against very small businesses. In other words, the ’648 patent has been issued to Troll Co. at 1 Troll Street, Troll Town, Trollida USA.

    We believe that the claims of the ’648 patent are clearly invalid under the Supreme Court’s decision in Alice v. CLS Bank, which held abstract ideas do not become eligible for a patent merely because they are implemented in conventional computer technology. Indeed, the patent repeatedly emphasizes that the claimed methods are not tied to any particular hardware or software. For example, it states:

    The software and software logic described in this document … which comprises an ordered listing of executable instructions for implementing logical functions, can be embodied in any non-transitory computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions.

    The ’648 patent issued on June 30, 2015, a full year after the Supreme Court’s Alice ruling. Despite this, the patent examiner never even discussed the decision. If Alice is to mean anything at all, it has to be applied to an application like this one.

    In our view, if Motivational Health Messaging asserts its patent in court, any defendant that fought back should prevail under Alice. Indeed, we would hope that the court would strongly consider awarding attorney’s fees to the defendant in such a case. Shipping & Transit has now had two fee awards made against it for asserting patents that are clearly invalid under Alice. And the Federal Circuit recently held that fee awards can be appropriate when patent owners make objectively unreasonable argument concerning Alice.

    In addition to the problems under Alice, we believe the claims of the ’648 patent should have been rejected as obvious. When the application was filed in 2012, there was nothing new about sending motivational messages or automatically tailoring messages to things like location. In one proposed embodiment, the patent suggests that a “user walking to a hole may be delivered ABS messages, including reminders or instructions on how to play a particular hole.” But golf apps were already doing this. The Patent Office didn’t consider any real-world mobile phone applications when reviewing the application.

    If you want to look for prior art yourself, Unified Patents is running a crowdsourcing contest to find the best prior art to invalidate the ’648 patent. Aside from the warm feelings that come from fighting patent trolls, there is a $2000 prize pool.

    Despite the weakness of its patent, Motivational Health Messaging LLC might still send out demand letters. If you receive such a letter, you can contact EFF and we can help you find counsel.

    We have long complained that the Patent Office promotes patent trolling by granting obvious and/or abstract software patents. The history of the ’648 patent shows how the Patent Office’s failure to properly review applications leads to bad patents falling into the hands of trolls.

    read more