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China's Censors Can Now Erase Images Mid-Transmission (wsj.com)

Posted by msmash on from the controlling-your-reality dept.

Eva Dou, reporting for WSJ: China's already formidable internet censors have demonstrated a new strength -- the ability to delete images in one-on-one chats as they are being transmitted, making them disappear before receivers see them. The ability is part of a broader technology push by Beijing's censors to step up surveillance and get ahead of activists and others communicating online in China (Editor's note: the link could be paywalled; alternative source). Displays of this new image-filtering capability kicked into high gear last week as Chinese dissident Liu Xiaobo lay dying from liver cancer and politically minded Chinese tried to pay tribute to him, according to activists and a new research report. Wu Yangwei, a friend of the long-jailed Nobel Peace Prize laureate, said he used popular messaging app WeChat to send friends a photo of a haggard Mr. Liu embracing his wife. Mr. Wu believed the transmissions were successful, but he said his friends never saw them. "Sometimes you can get around censors by rotating the photo," said Mr. Wu, a writer better known by his pen name, Ye Du. "But that doesn't always work." There were disruptions on Tuesday to another popular messaging app, Facebook's WhatsApp, with many China-based users saying they were unable to send photos and videos without the use of software that circumvents Chinese internet controls. Text messages appeared to be largely unaffected.

52 of 90 comments (clear)

  1. Well yeah by Ryanrule · · Score: 1

    weChat is run by the govt

    1. Re: Well yeah by Anonymous Coward · · Score: 1

      Here below is my attached meme image response:

      AC

    2. Re: Well yeah by KevinPrice · · Score: 1

      You do realize this means they have a CITM (computer in the middle. There aren't enough peeps to have an MITM or man in the middle of every internet connection). Once you find an image that is censored try sending it different ways with different communication methods. You will learn a lot. Does it get censored on Facebook messenger (does China allow FB messenger?). If so then FB gave them the encryption keys. Does the image get censored on a supposed secure SSL connection? If it does then think about that one! You can learn a lot by playing around with known blocked images. You should be able to do it from the USA by engaging Chinese websites and messenging systems if you have a Chinese person to chat with. I don't think the Chinese have realized the enormous implications of what they have done. I have just touched the surface.

  2. Aggressive post processing by magarity · · Score: 2

    Sufficient alterations such as running images through a "make it look like an oil painting" can probably get around this kind of detection. Although watch out for that "convert to cubism" option.

    1. Re:Aggressive post processing by 93+Escort+Wagon · · Score: 2

      Take it a step further, and use steganography.

      --
      #DeleteChrome
    2. Re:Aggressive post processing by Anonymous Coward · · Score: 1

      And then you can be "aggressively post-processed" by the Chinese government for subverting their censor.

      Scary stuff.

    3. Re:Aggressive post processing by R3d+M3rcury · · Score: 1

      ASCII Art FTW!

    4. Re:Aggressive post processing by wardrich86 · · Score: 1

      ANSI art is far superior.

    5. Re:Aggressive post processing by XXongo · · Score: 1

      Take it a step further, and use steganography.

      You mean encryption.

      steganography would be hiding bits within the image-- encryption would be hiding the image.

    6. Re:Aggressive post processing by Anonymous Coward · · Score: 1

      Hide the bits that make the original image within a different image.

    7. Re:Aggressive post processing by KiloByte · · Score: 1

      Try this: convert myimage.png.jpeg.xpm.tif.whatever tmp.ubrl && tail -n+4 tmp.ubrl

      Then paste into any text medium that has been updated this millenium (ie, not Slashdot). Resolution is 2x4 per character, black&white only.

      --
      The creatures outside looked from Alt-Right to Antifa; but already it was impossible to say which was which.
  3. OMG... by __aaclcg7560 · · Score: 3, Interesting

    What did Winnie the Pooh ever do to the Chinese government?

    https://www.nytimes.com/2017/07/17/world/asia/china-winnie-the-pooh-censored.html

    1. Re:OMG... by Anonymous Coward · · Score: 1

      The good thing about Chinese censorship is that at least a billion people will be spared your ebooks. Can you imagine a Chinese kid learning English and the first thing they find is a cdreimer extravaganza? That'll make the Tyco suicides look like a walk in the park!

      BTW: How come you didn't provide any certificates of destruction for the hard disks on the 100 laptops you sold to a recycler? I bet future employers would like to know what you do with their property?

  4. Well... by Anonymous Coward · · Score: 5, Insightful

    ...guess it won't be long before this comes to the UK.

    For the children, don't you know?

    1. Re:Well... by Anonymous Coward · · Score: 1

      Well, yes. They have to protect the Muslims as they know they will be in power. It's a giant fucking race to cater to the new demographics so as to stay politically relevant. Sharia law is de-factor legal now.

  5. in soviet russia we erase you! by Joe_Dragon · · Score: 1

    in soviet russia we erase you!

  6. Re:Wonder which will happen first: by Ryanrule · · Score: 1

    When their bubble bursts. So, soon.

  7. free for all by Anonymous Coward · · Score: 1

    they should totally open-source this code.
    this way everybody can start erasing their own picture if taken by 3rd party and posted to facebook etc. without their consent.
    call it: "take-back-privacy"

  8. Eh... by Travelsonic · · Score: 1

    Tell me, how do they intercept the data, figure out what it is - and how they get around disguising the data in so far as possibly stripping out any headers identifying file types, and the like for instance (without which, would seemingly just appear as a string of 1s and 0s).

    --
    If you believe in privacy, and believe you have "nothing to hide" at the same time, you're a goddammed idiot
    1. Re:Eh... by Anonymous Coward · · Score: 1

      This is all done server-side.

      Wechat, the app in question, sends and stores all messages on Wechat's servers before broadcasting it to the intended recipients.

      According to various news reports, they've been able to trigger review of message via keyword-based messages for quite a while, and now they've apparently added the ability to filter videos and images by comparing them for similarities to banned images.

      One thing to remember about this is, Wechat is a major payment/messaging/blogging platform inside China, so the government being able to censor stuff in a semi-automated fashion means effectively, most activities are logged and censored automatically.

    2. Re:Eh... by dgatwood · · Score: 1

      I would not be at all surprised if sharing photos amounts to sharing the URL for the photo, in effect, in which case it can be blocked merely by blocking the URL (assuming no HTTPS).

      --

      Check out my sci-fi/humor trilogy at PatriotsBooks.

    3. Re:Eh... by myowntrueself · · Score: 1

      it can't be that much harder than the upside-down-ternet:
      http://www.ex-parrot.com/pete/...

      when you have sufficient processing power.

      I've actually implemented this on a MITM proxy server with its trusted root certificate being installed via group policy so I could manipulate images on the fly and deliver things like downgraded image quality based on AD group membership. And its all HTTPS and the certificate checks out (on face value to the plebs, at least it doesn't give a warning in the browser) so thats how the images must be supposed to look, right?

      If the workstation wasn't in the domain then they'd get yet another different version of the Internet but of course the certificate doesn't check out because the group policy hasn't forced their workstation to trust it.

      My employer asked me to do it. And this wasn't in China. If it were China then their computer would trust the certificate and I could do even more fiendish things with their images, on the fly.

      --
      In the free world the media isn't government run; the government is media run.
    4. Re:Eh... by AHuxley · · Score: 1

      The same way the NSA and GCHQ do it. A race track with consumer data going the long way around getting altered by faster gov/security services.
      FoxAcid, Turmoil, Quantum, QuantumInsert. Man-on-the-side, man-in-the-middle outpace any consumer network. Why just collect information on the way when the results can be changed too?
      Just as the NSA and GCHQ know all about peering, every server and service provider and the fast speed of their own tame telcos, so does China.
      The only way around that would be a good VPN. But VPN use would be detected given the network origin in China and discovered encrypted response of a destination VPN server outside China.

      --
      Domestic spying is now "Benign Information Gathering"
  9. Pay-Walled Source? by Frosty+Piss · · Score: 1

    If the story source is pay-walled (and here's an alturnative source), why refer and list the pay-walled link at all? Why not just use the alturnative source as the primary source?

    --
    If you want news from today, you have to come back tomorrow.
    1. Re:Pay-Walled Source? by XXongo · · Score: 2
      Because the alternative source is not the primary source. It is a mirror of the primary source.

      (Also, often the mirrors are on less-robust servers, so it's nice to have the primary source available for when the mirror inexplicably gets slashdotted.)

  10. steganography? by roc97007 · · Score: 3, Insightful

    I'm curious if they've tried steganography to get around censorship? Hiding the photo inside another photo or document?

    Or maybe they *are* doing that, and the reason we're not hearing about it is because it's working.

    So... never mind...

    --
    Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
    1. Re:steganography? by Falos · · Score: 1

      Some, probably. The masses probably use easier "tricks" like rotation. Those are easier moles to whack, but it's still whack-a-mole and still futile and the tools of commoners will nestle in the classic feedback valley that balances 1) method difficulty, obscurity, resilience (whack cost); vs 2) likelihood/frequency of mole whack from Our Betters

      I've heard that they'll use substitute words to dodge filters. When they want to refer to a certain politician, location, event (tiananmen square?) they'll carefully choose words that sound similar, or use a visually-similar kanji script. Naturally there will be a list of regulars (eg "emperor cheeto") that circulate, then overcirculate and get whacked, to be reborn with a new substitution.

    2. Re:steganography? by TheNarrator · · Score: 1

      The technology is about suppressing what people of average intelligence get to see, not what people who are technologically sophisticated get to see.

    3. Re:steganography? by roc97007 · · Score: 3, Interesting

      Well, ok, your questions sound rhetorical, so this will probably be unwelcome, but I think the difference is intent.

      In the US it's done for a variety of reasons -- intellectual property, porn, unlawful content, politically incorrect (ahem-facebook), and in China it's specifically targeted at political dissidents. Here we can say Apple (or Microsoft if that makes you more comfortable) is being a dick, I'll use some other service. Over there it's more problematic, because (a) it's the government doing it (yeah, I know, bear with me) *and* (b) it's specifically targeted at anti-government speech. Which we would call, over here, free speech.

      So over here someone can post a photo holding the bloody decapitated head of the president... no wait, that's a bad example... no, on further thought, it's a valid example. She was able to post the image without having it deleted by the government. Other bad things happened, but government deletion in transit wasn't one of them.

      So, I'd argue, not hypocritical at all. Freedom and privacy are complex issues, and I don't think there's anyone within the sound of my voice that believes we in the US have complete freedom. Whether we should or not would be a lively discussion. But I think we can agree that people in china have much less freedom.

      --
      Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
    4. Re:steganography? by roc97007 · · Score: 1

      You are absolutely right. That's an excellent point. So perhaps what's needed are some easy to use tools that allow average people to use sophisticated techniques.

      --
      Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
    5. Re:steganography? by umafuckit · · Score: 1

      Perhaps, but the sort of censorship we're seeing here is just a heavy-handed way of attempting to steer discussion on social media and chat apps. The other thing they did recently was remove is a load of foreign material from bilibili.com/, which is a Chinese video sharing site with subtitles and viewer commentary.

      If you really want to secretly share an image, there are a bunch of ways of doing that. What you're seeing with these recent actions are attempts to push around the most number of people with the least effort.

      --
      soylentnews.org
    6. Re:steganography? by roc97007 · · Score: 1

      OMG. Are you telling us that steganography is the reason why there are so many pictures of cats on the Internet?

      No of course n... wait... Wow. That's... actually pretty insightful.

      --
      Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
    7. Re:steganography? by Anonymous Coward · · Score: 1

      You are absolutely right. That's an excellent point. So perhaps what's needed are some easy to use tools that allow average people to use sophisticated techniques.

      Then, and therein lies the fun, whoever builds and distributes that tool is an enemy of the state.

      When the law is "whatever I say", there's no loophole.

    8. Re:steganography? by roc97007 · · Score: 1

      You are absolutely right. That's an excellent point. So perhaps what's needed are some easy to use tools that allow average people to use sophisticated techniques.

      Then, and therein lies the fun, whoever builds and distributes that tool is an enemy of the state.

      When the law is "whatever I say", there's no loophole.

      I think one could argue that using any method to circumvent censorship by the glorious people's republic of China, including perhaps even rotating the image, could make one an enemy of the state. Why not go for the gusto?

      --
      Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
  11. One way they might do it by Zontar_Thing_From_Ve · · Score: 1

    Tell me, how do they intercept the data, figure out what it is - and how they get around disguising the data in so far as possibly stripping out any headers identifying file types ...

    I know one way they could do it. People assume this censorship applies to everybody in China, but it could actually be restricted and implemented in a real low tech way that makes people think it applies to everybody when it only applies to a select few. Imagine a Man In The Middle approach. It seems logical to me that certain users are likely known by the government to post objectionable things from time to time, so if you don't have an exceptionally large number of such people to keep an eye on, you could implement a MITM approach and send all their communications through a central party I'll call a "watcher" who sees the communication in real time and has the ability to pass on the communication untouched and also has the ability to edit out objectionable content before passing it on. Maybe the spied on person only uses WeChat for, say, 30 minutes, so the watcher moves on at the end of that to another user. You could just restrict the watchers to say 100 or maybe 1000 such people and if you make sure they watch the people who consistently post the most objectionable content (yet never advocate overthrown of the government as that would get them arrested and no need to watch them anymore), you could certainly keep tabs on those few individuals They'll figure it out and complain and then everybody assumes that everybody is being watched when in fact you're doing this as low tech as possible with big time human intervention needed and people just assume some massively smart and obtrusive computer program is scanning literally everything. We have had people here on Slashdot who honestly believe the US government has people who read every email sent by every person in the USA, so all it would take is a few Chinese users to complain about this and the government laughs as the sheeple get too scared to do anything controversial and the actual scope of the watching is far lower than suspected.

    1. Re:One way they might do it by pz · · Score: 1

      ... you could implement a MITM approach and send all their communications through a central party I'll call a "watcher" who sees the communication in real time and has the ability to pass on the communication untouched and also has the ability to edit out objectionable content before passing it on. Maybe the spied on person only uses WeChat for, say, 30 minutes, so the watcher moves on at the end of that to another user. You could just restrict the watchers to say 100 or maybe 1000 such people and if you make sure they watch the people who consistently post the most objectionable content ...

      A Scanner Darkly!

      --

      Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
  12. Re:Censorship in the U.S. by Anonymous Coward · · Score: 1

    As I will now demonstrate:

    Moderation is not the same as censorship. Learn the difference.

  13. Life imitating art by pz · · Score: 1

    Once again, Mr. Munroe gets it right well before his time.

    https://xkcd.com/341/

    --

    Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
  14. Re:The UK is going much further to censor the net by computational+super · · Score: 1

    I've begun to lose hope that the world will ever realize that censorship is all or nothing - if you support censorship of anything, for any reason, you're implicitly (whether you intend to or not) support censorship of any other thing. If we all, as a populace, reject censorship outright, they can never censor us. If we accept it in any form, it will always grow.

    --
    Proud neuron in the Slashdot hivemind since 2002.
  15. Re:The UK is going much further to censor the net by Topwiz · · Score: 2

    Yet they allow topless pictures of large breasted women in regular newspapers.

  16. AI world takeover by Gilgaron · · Score: 1

    Most fiction has the apocalyptic AI that takes over be of military origin, but I'm thinking it is going to be a Chinese AI that decides the best way to censor communications is to Kill All Humans.

  17. Re:Censorship in the U.S. by Anonymous Coward · · Score: 1

    Moderation is not the same as censorship.

    Is that newspeak?

  18. Re:Liberals by interkin3tic · · Score: 4, Informative

    The left wing in various contexts throughout history can censor things, yes, but here in the US at the moment? The right wing is the one that is in any power. States, federal, media... the struggle is between far right and center. We're debating how much religious organizations are allowed to discriminate against gays and contribute to political campaigns, not whether or not they should be taxed and prevented from addressing politics. There's a ban on federal funds going to health organizations that mention the word "abortion."

    The closest thing I can see to left-wing censorship is a handful of relatively powerless college students acting rashly. And in each of those cases, the conservative outrage has been many times greater in magnitude.

    Liberals and centrists sitting on the fence and saying "Now now, both sides can be equally bad" when clearly they're not BEING anywhere near equally bad is what's causing us to run into disaster.

  19. Text messages appeared to be unaffected by WillAffleckUW · · Score: 1

    Are you sure?

    Don't count on it.

    And you thought AI was your friend ...

    --
    -- Tigger warning: This post may contain tiggers! --
  20. Re:The UK is going much further to censor the net by WillAffleckUW · · Score: 1

    That's The Doctor, n00b

    --
    -- Tigger warning: This post may contain tiggers! --
  21. Re:Liberals by Anonymous Coward · · Score: 1

    The left wing in various contexts throughout history can censor things, yes, but here in the US at the moment? The right wing is the one that is in any power. ...

    Riiiight.

    It's those conservative right-wingers that use violence as a heckler's veto to chase "progressive" speakers off of college campuses.

    Oh, wait, I was wrong.

    It's self-styled "PROGRESSIVES" that go around actually engaging in political violence by "punching Nazis". (Well, they try to - the candy-ass metrosexual wimps usually get their asses kicked - just Google "moldylocks gets punched". Oh, wait, I did it for you! BWAA HAAA HAAAA!!!!)

    It's "PROGRESSIVES" who go around shutting down speakers they don't agree with for the simple act of daring to say things they don't agree with.

    It's "PROGRESSIVES" who glorify political violence - any pay homage to fanatic Islam - by severing the head of President Trump.

    So we can conclude that, just like most hard-left idiocy, "progress" involves not just censorship but actual political violence.

  22. Re:Liberals by Anonymous Coward · · Score: 1

    And the Right condones blowing up governments that don't agree with them. See :Oklahoma City Bombing.

    See? I can equate one person with the whole wing too!

  23. Actually Steganography Better by Roger+W+Moore · · Score: 2

    In this application, steganography is probably better. Encrypted data is generally easy to spot and ban - China has already banned VPNs. However, with steganography, you can have what looks like an ordinary picture containing the data for the picture that you actually want to send. Since this looks just like an ordinary image unless they block the transmission of all images it should get through.

  24. Re:Liberals by wyHunter · · Score: 1

    I'd be curious to find out what planet you live on.

  25. Re:Liberals by interkin3tic · · Score: 1

    There have literally been over a thousand cataloged attacks from the right wing since the election.

    Attacks from liberals on conservatives have been fewer, the chart one month goes up to ten!

    The left wing violence list includes things like "throwing eggs" while the right wing violence list has "throwing acid."

    I'm sure there are better sources for this information out there and I'm interested if anyone has any. I just did a quick google search on both.

    At any rate, I can't fathom anyone who suggests violent college students are a serious threat. They're far less scary than Islamic terrorists, which are themselves factually less dangerous than armed toddlers. Don't be an asshole racist demagogue and go to the most wildly liberal campus in the united states and you'll have nothing to fear from college progressives.

    Or do even! Not a goddamn hair on Milo or Coulters' heads were harmed! Fucking snowflakes...

  26. Re: Liberals by KGIII · · Score: 1

    I believe the discussion is about current events.

    --
    "So long and thanks for all the fish."
  27. Re: Censorship in the U.S. by KGIII · · Score: 1

    To be fair, I see the original post. I browse at -1, of course.

    --
    "So long and thanks for all the fish."